Operation of Functions

Teacher Espie TV
3 Aug 202008:18

Summary

TLDRIn this educational video, Teacher SP explains the four fundamental operations of functions: addition, subtraction, multiplication, and division. The video provides clear examples of how to evaluate these operations, emphasizing the importance of not dividing by zero. The teacher demonstrates with functions f(x) = x - 3 and g(x) = x + 5, showing how to perform the operations and simplify the results. The lesson is designed to help viewers understand and apply these operations to functions effectively.

Takeaways

  • 📚 The video discusses the fundamental operations of functions, focusing on addition, subtraction, multiplication, and division.
  • 🔢 Addition of functions is defined as the sum of f(x) and g(x), represented as f(x) + g(x).
  • ➖ Subtraction of functions is defined as the difference of f(x) and g(x), represented as f(x) - g(x).
  • 🔄 Multiplication of functions is defined as the product of f(x) and g(x), represented as f(x) * g(x).
  • 🔄 Division of functions is defined as the quotient of f(x) and g(x), represented as f(x) / g(x), with the caveat that g(x) cannot be zero to avoid undefined results.
  • ❌ Division by zero is emphasized as undefined, using the example of eight divided by zero.
  • 📘 An example is provided to demonstrate the operations: f(x) = x - 3 and g(x) = x + 5, showing how to apply the four operations.
  • 🧮 For addition, the example simplifies to 2x + 2, and then factors out to 2(x + 1).
  • 📉 For subtraction, the example results in -8 after applying the rules of integer subtraction.
  • 📊 For multiplication, the example uses the FOIL method for binomials, resulting in x^2 + 2x - 15.
  • 📌 For division, the example shows that binomials cannot be directly divided or cancelled out in the context of the operations discussed.

Q & A

  • What are the four fundamental operations of functions?

    -The four fundamental operations of functions are addition, subtraction, multiplication, and division.

  • How is the sum of two functions f(x) and g(x) defined?

    -The sum of two functions f(x) and g(x) is defined as f(x) + g(x).

  • What is the difference between the functions f(x) and g(x) when f(x) is 10 and g(x) is 2?

    -The difference between the functions f(x) and g(x) when f(x) is 10 and g(x) is 2 is 8, as 10 - 2 equals 8.

  • What is the product of the functions f(x) and g(x) when f(x) is 3 and g(x) is 5?

    -The product of the functions f(x) and g(x) when f(x) is 3 and g(x) is 5 is 15, as 3 times 5 equals 15.

  • Why is division by g(x) not allowed when g(x) equals zero?

    -Division by g(x) is not allowed when g(x) equals zero because it results in an undefined expression, as division by zero is undefined in mathematics.

  • What is the result when you add the functions f(x) = x - 3 and g(x) = x + 5?

    -The result when you add the functions f(x) = x - 3 and g(x) = x + 5 is 2x + 2, after simplifying the expression.

  • How do you find the difference between the functions f(x) = x - 3 and g(x) = x + 5?

    -To find the difference between the functions f(x) = x - 3 and g(x) = x + 5, you subtract g(x) from f(x), resulting in -8 after applying the subtraction rules.

  • What is the product of the binomials (x - 3) and (x + 5) using the FOIL method?

    -Using the FOIL method, the product of the binomials (x - 3) and (x + 5) is x^2 - 3x + 5x - 15, which simplifies to x^2 + 2x - 15.

  • Why can't you directly divide the binomials (x - 3) by (x + 5)?

    -You can't directly divide the binomials (x - 3) by (x + 5) because they are not in a form that allows for simple cancellation or direct division as they are both binomials.

  • What is the final simplified form of the expression 2x + 2 after factoring out the common factor?

    -The final simplified form of the expression 2x + 2 after factoring out the common factor 2 is 2(x + 1).

Outlines

00:00

📘 Introduction to Operations of Functions

Teacher SP begins the video by welcoming viewers back to the channel and encourages them to subscribe, like, comment, and enable notifications. The main topic of the video is the fundamental operations of functions, which include addition, subtraction, multiplication, and division. The instructor explains each operation using simple arithmetic examples and then relates them to functions. For addition, the sum of functions f(x) and g(x) is defined as f(x) + g(x). For subtraction, it's f(x) - g(x), for multiplication, it's f(x) * g(x), and for division, it's f(x) / g(x), with the caveat that g(x) must not equal zero to avoid undefined results. The instructor also clarifies why division by zero is undefined using an example of eight divided by zero. The video aims to provide a clear understanding of how to evaluate these operations with functions.

05:01

🔢 Applying Operations to Functions

In this segment, the instructor applies the four fundamental operations to specific functions f(x) = x - 3 and g(x) = x + 5. For addition, the instructor combines the functions to get (x - 3) + (x + 5), which simplifies to 2x + 2. The common factor of 2 is then factored out, resulting in the final answer of 2(x + 1). For subtraction, the instructor follows the rule of changing the sign of the subtrahend, leading to the result of -8 after simplification. For multiplication, the FOIL method is used to multiply (x - 3) and (x + 5), resulting in x^2 - 3x + 5x - 15, which simplifies to x^2 + 2x - 15. Lastly, for division, the instructor notes that the binomials (x - 3) and (x + 5) cannot be directly divided or canceled out, indicating that the expression stands as the final answer for division. The video concludes with a reminder that the next lesson will cover more complex equations involving these operations.

Mindmap

Keywords

💡Operations of Functions

Operations of functions refer to the mathematical procedures that can be performed on functions, such as addition, subtraction, multiplication, and division. In the video, the teacher explains how to evaluate these operations, using them to combine two functions, f(x) and g(x). This concept is central to the video's theme as it lays the foundation for understanding how functions can be manipulated and interact with one another.

💡Addition

Addition, in the context of functions, is the process of adding two functions together. The video provides an example where the sum of f(x) and g(x) is defined as f(x) + g(x). This operation is fundamental in algebra and calculus, allowing for the construction of new functions by combining existing ones.

💡Subtraction

Subtraction of functions is the process of subtracting one function from another, defined as f(x) - g(x). The video script uses the example of 10 minus 2 to illustrate this concept, highlighting that subtraction is used to find the difference between the values of two functions.

💡Multiplication

Multiplication of functions, as explained in the video, is the process of multiplying two functions together, resulting in a new function defined as f(x) * g(x). The script uses the multiplication of 3 and 5 to equal 15 to exemplify this, showing how it relates to scaling the output of one function by the output of another.

💡Division

Division of functions involves dividing one function by another, defined as f(x) / g(x), provided that g(x) is not equal to zero. The video emphasizes the importance of the divisor not being zero, as division by zero is undefined in mathematics. This operation is crucial for understanding how the ratio of two functions can result in a new function.

💡Undefined

The term 'undefined' in the video refers to a mathematical expression that does not have a value. Specifically, division by zero is highlighted as undefined because it does not produce a meaningful result. The script uses the example of eight divided by zero to illustrate this concept, which is a critical aspect of function operations to avoid errors in calculations.

💡Binomials

Binomials are algebraic expressions consisting of two terms. In the video, the teacher discusses how to multiply binomials, such as (x - 3) and (x + 5), using the FOIL method (First, Outer, Inner, Last). This is a key algebraic skill that is essential for understanding the multiplication of functions.

💡FOIL Method

The FOIL method is a mnemonic for multiplying two binomials. The video script demonstrates the FOIL method by multiplying x - 3 and x + 5, which results in the expansion of the product to x^2 - 3x + 5x - 15. This method is a fundamental technique in algebra for simplifying the product of binomials.

💡Common Factor

A common factor is a term or expression that is shared between two or more terms in a polynomial. In the video, the teacher identifies 2 as a common factor in the expression 2x + 2 and simplifies it to 2(x + 1). This concept is important for factoring and simplifying expressions in algebra.

💡Cancellation

Cancellation in the context of the video refers to the process of simplifying an expression by eliminating common terms. The script mentions that when subtracting x - 3 from x + 5, the x terms cancel out, resulting in -8. This technique is used to simplify expressions and is a key concept in algebra.

💡Fundamental Operations

Fundamental operations encompass the basic mathematical procedures of addition, subtraction, multiplication, and division. The video uses these operations to demonstrate how to work with functions. Understanding these operations is essential for grasping more complex mathematical concepts and for performing calculations involving functions.

Highlights

Introduction to the concept of operations of functions.

Definition of the four fundamental operations of functions: addition, subtraction, multiplication, and division.

Explanation of addition of functions with an example of 3 + 8 = 11.

Definition of the sum of functions f(x) + g(x).

Explanation of subtraction of functions with an example of 10 - 2 = 8.

Definition of the difference of functions f(x) - g(x).

Explanation of multiplication of functions with an example of 3 * 5 = 15.

Definition of the product of functions f(x) * g(x).

Explanation of division of functions with an example of 16 / 2 = 8 and the importance of g(x) ≠ 0.

Definition of the quotient of functions f(x) / g(x) with the condition g(x) ≠ 0.

Example of applying the four operations to functions f(x) = x - 3 and g(x) = x + 5.

Calculation of f(x) + g(x) resulting in 2x + 2 and simplification to 2(x + 1).

Calculation of f(x) - g(x) resulting in -8 after simplification.

Application of the FOIL method to multiply (x - 3) and (x + 5).

Result of the multiplication (x - 3)(x + 5) leading to x^2 - 3x + 5x - 15.

Explanation of why division of binomials (x - 3) / (x + 5) cannot be simplified.

Conclusion of the lesson and a teaser for the next lesson on more complex operations.

Transcripts

play00:02

good evening everyone

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this is teacher sp and welcome back to

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my channel

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sucking channel mug subscribe like

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comment and hit the notification bell so

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that you will be updated for whatever

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videos i'm going to upload

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so you guys

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i what we call operations of functions

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how to evaluate the function right

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and for fundamental operation now

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function

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we know that there are four fundamental

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operations of functions

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and these are addition subtraction

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multiplication and division now

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let us proceed to the concept of this

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four

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fundamental operation so like for

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example

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if i will be giving three plus

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eight then the answer is equal to eleven

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so this is what we call addition what do

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you call

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three and eight so we call this

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our add-ins okay

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so 3 and 8 and this 11

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is what we call the sum so therefore

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the sum of f

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of x and g of x

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is defined as f

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of x plus g

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of x so this is now

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the formula for the operation addition

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of function

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how about this 10 minus 2

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so we know that 10 minus 2 is equal to 8

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so let us identify

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10 is what we call the min win and 2

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is what we call the subtrohen and what

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do you call 8

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8 is what we call the difference so

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therefore

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f of x and g of

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x is defined as okay

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the difference of f of x

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minus g of x

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okay and let us proceed now to number

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three

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three times five that is equal to

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15. so what do you call three and

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five so three and five are what we call

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the factors

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and is what we call the product

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so therefore the product

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of f of x and g of x

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is defined as f of x

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times g of x

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okay but how about this one 16

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divided by two is equal to eight

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16 is what we call the dividend

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2 is what we call the divisor and 8 is

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what we call the quotient

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so therefore the quotient of

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f of x and g of x

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is defined as f of

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x over g

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of x such that

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g of x is not equal to

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zero why bakit na ang atting g

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of x is not equal to zero guys because

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say

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kappa zero and denominator mo the answer

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is what we call undefined okay let us

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prove for example

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eight over

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zero is undefined okay if your answer is

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zero

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zero times zero is equal to zero so we

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know that this is

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eight capacitor

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so therefore all the numbers that the

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denominator is

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zero that is what we call the undefined

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so these

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are now the four operations the formula

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of the four operations of functions okay

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i will be giving you an example and we

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will be using

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this for operations

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okay for example find

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the value of

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f of x is equal to x

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minus 3 g of x

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is equal to x plus 5

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using the four operations of functions

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so therefore

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so using f of x plus g

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of x so x

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minus 3 x plus 5

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then negative 3 and positive 5

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that is equal to positive 2 x

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and x so one plus one that is equal to

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two x

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plus two is this now our final answer

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hindi fatto final answer nothing guys

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we are going to get the common factor of

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this

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so therefore the common factor is 2

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okay 2x divided by 2 that is equal to x

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plus 2 divided by 2 is equal to 1.

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so therefore the final answer is 2

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times the quantity of x plus 1

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okay now next is we are going to

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subtract

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x minus 3 and x

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plus 5 so in subtracting this number

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guys

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so we have to follow the rule in

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subtracting an

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integer so the rule says that you are

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going to change

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the sign of the subtrahend and we know

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that x plus 5 is the subtrahend

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so therefore positive by gigi negative

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positive becomes negative so negative 3

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and negative 5 that is equal to negative

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8

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and positive x and negative x cancel ion

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so therefore

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the answer is equal to negative eight

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okay so how about number three

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okay number three is what we call

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multiplication so we are going to

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multiply

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these two binomials x minus 3

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and x plus 5 using

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a foil method right so x times x that is

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equal to

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x squared negative 3

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times x is equal to negative 3x

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outer term is x times 5 that is equal to

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5x

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combine it together that will be equal

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to

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positive 2x okay

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negative 3 times positive 5

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is equal to negative 15. so therefore

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this is now

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the answer for the multiplication this

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is now the product okay now let us

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proceed letter

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d which is the division so x

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minus three okay divided by

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x plus five you cannot divide this two

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they are binomials you cannot also

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use the cancellation method so therefore

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this is now the answer using

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the four fundamental operations of

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functions

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so i hope that uh you uh learn something

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today

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and for the next lesson we will be

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proceeding or i will be explaining

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the four fundamental operations but it's

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a complicated

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equation so thank you so much guys

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and have a great day everyone

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