Factored form of the quadratic function

This form is called factored because it uses the factors of a multiplication.

With this form, we can easily identify the points of intersection of the function with the XX axis.
The factored form of the quadratic function looks like this:
y=(xt)×(xk)y=(x-t) \times (x-k)

Suggested Topics to Practice in Advance

  1. Standard Form of the Quadratic Function

Practice Product Representation

Examples with solutions for Product Representation

Exercise #1

Find the standard representation of the following function

f(x)=(x2)(x+5) f(x)=(x-2)(x+5)

Video Solution

Step-by-Step Solution

We will begin by using the distributive property in order to expand the following expression.

(a+1)⋆(b+2) = ab+2a+b+2

We will then proceed to insert the known values into the equation and solve as follows:

(x-2)(x+5) =

x²-2x+5x+-2*5=

x²+3x-10

And that's the solution!

Answer

f(x)+x2+3x10 f(x)+x^2+3x-10

Exercise #2

Find the standard representation of the following function

f(x)=(x6)(x2) f(x)=(x-6)(x-2)

Video Solution

Step-by-Step Solution

To find the standard representation of the quadratic function f(x)=(x6)(x2) f(x) = (x - 6)(x - 2) , follow these steps:

  • Step 1: Apply the FOIL method to expand the expression.
    - First: Multiply the first terms: x×x=x2 x \times x = x^2 .
    - Outside: Multiply the outer terms: x×(2)=2x x \times (-2) = -2x .
    - Inside: Multiply the inner terms: (6)×x=6x (-6) \times x = -6x .
    - Last: Multiply the last terms: (6)×(2)=12 (-6) \times (-2) = 12 .
  • Step 2: Combine the results from the FOIL method.
    - Combine all the expanded terms: x22x6x+12 x^2 - 2x - 6x + 12 .
  • Step 3: Simplify by combining like terms.
    - Combine the x x -terms: 2x6x=8x -2x - 6x = -8x .
    - The expanded and simplified form is: f(x)=x28x+12 f(x) = x^2 - 8x + 12 .

By expanding and simplifying the given product, we have converted it to its standard form. Therefore, the standard representation of the function is f(x)=x28x+12 f(x) = x^2 - 8x + 12 .

The correct choice from the provided options is choice 2: f(x)=x28x+12 f(x) = x^2 - 8x + 12 .

Answer

f(x)=x28x+12 f(x)=x^2-8x+12

Exercise #3

Find the standard representation of the following function

f(x)=(x+2)(x4) f(x)=(x+2)(x-4)

Video Solution

Step-by-Step Solution

To find the standard representation of the quadratic function given by f(x)=(x+2)(x4) f(x) = (x+2)(x-4) , we will expand the expression using the distributive property, commonly known as the FOIL method (First, Outer, Inner, Last):

  • First: Multiply the first terms in each binomial: xx=x2 x \cdot x = x^2 .
  • Outer: Multiply the outer terms in the binomials: x(4)=4x x \cdot (-4) = -4x .
  • Inner: Multiply the inner terms: 2x=2x 2 \cdot x = 2x .
  • Last: Multiply the last terms in each binomial: 2(4)=8 2 \cdot (-4) = -8 .

Now, let's combine these results:

The expression becomes x24x+2x8 x^2 - 4x + 2x - 8 .

Next, we combine like terms:

The terms involving x x are 4x+2x -4x + 2x , which simplifies to 2x -2x .

Thus, the expression simplifies to: f(x)=x22x8 f(x) = x^2 - 2x - 8

Upon comparing this result to the provided choices, we find that it matches choice 3.

Therefore, the standard representation of the function is f(x)=x22x8 f(x) = x^2 - 2x - 8 .

Answer

f(x)=x22x8 f(x)=x^2-2x-8

Exercise #4

Find the standard representation of the following function

f(x)=3x(x+4) f(x)=3x(x+4)

Video Solution

Step-by-Step Solution

To find the standard representation of the quadratic function f(x)=3x(x+4) f(x) = 3x(x + 4) , follow these steps:

  • Step 1: Apply the distributive property to expand the expression x(x+4) x(x + 4) .
    Using this property, we have:
    x(x+4)=xx+x4=x2+4x x(x + 4) = x \cdot x + x \cdot 4 = x^2 + 4x .
  • Step 2: Multiply each term by the coefficient outside the parenthesis, which is 3.
    This gives us:
    3(x2+4x)=3x2+34x 3(x^2 + 4x) = 3 \cdot x^2 + 3 \cdot 4x .
  • Step 3: Simplify by performing the multiplication.
    3x2+12x 3x^2 + 12x .

Therefore, the standard representation of the function is f(x)=3x2+12x f(x) = 3x^2 + 12x . This matches choice 3 in the provided answers.

Answer

f(x)=3x2+12x f(x)=3x^2+12x

Exercise #5

Find the standard representation of the following function

f(x)=x(x8) f(x)=-x(x-8)

Video Solution

Step-by-Step Solution

To solve this problem, we'll convert the given function from its factored form to the standard form using the distributive property. The given function is f(x)=x(x8) f(x) = -x(x - 8) .

Let's go through the necessary steps:

  • Step 1: Apply the distributive property to expand the expression.
    f(x)=x(x8)=xx+(x)(8) f(x) = -x(x - 8) = -x \cdot x + (-x) \cdot (-8)
  • Step 2: Simplify each term.
    xx=x2-x \cdot x = -x^2 and (x)(8)=+8x(-x) \cdot (-8) = +8x.
  • Step 3: Combine the terms to express f(x) f(x) in standard form:
    f(x)=x2+8x f(x) = -x^2 + 8x .

Therefore, the standard representation of the function is f(x)=x2+8x f(x) = -x^2 + 8x .

Comparing this result to the multiple-choice options, we can see that the correct choice is option 3: f(x)=x2+8x f(x)=-x^2+8x .

Answer

f(x)=x2+8x f(x)=-x^2+8x

Exercise #6

Find the standard representation of the following function

f(x)=(x+1)(x1) f(x)=(x+1)(x-1)

Video Solution

Step-by-Step Solution

To solve this problem and find the standard representation of the function f(x)=(x+1)(x1) f(x) = (x+1)(x-1) , we will expand the product using the distributive property, often recalled as FOIL (First, Outer, Inner, Last) for the product of two binomials.

Let's proceed step-by-step:

  • Step 1: Apply the distributive property:
    f(x)=(x+1)(x1) f(x) = (x+1)(x-1) would become:
  • First terms: xx=x2 x \cdot x = x^2
  • Outer terms: x(1)=x x \cdot (-1) = -x
  • Inner terms: 1x=x 1 \cdot x = x
  • Last terms: 1(1)=1 1 \cdot (-1) = -1

Step 2: Combine all the terms obtained from the FOIL method:
x2x+x1 x^2 - x + x - 1

Step 3: Simplify the expression by combining like terms:
The terms x-x and xx cancel each other out, simplifying to:
f(x)=x21 f(x) = x^2 - 1

Thus, the standard representation of the function is f(x)=x21 f(x) = x^2 - 1 .

Answer

f(x)=x21 f(x)=x^2-1

Exercise #7

Find the standard representation of the following function

f(x)=(2x+1)(x2) f(x)=(2x+1)(x-2)

Video Solution

Step-by-Step Solution

To find the standard representation of the function f(x)=(2x+1)(x2) f(x) = (2x + 1)(x - 2) , we'll follow these steps to expand and simplify the expression:

  • Step 1: Distribute each term of the first binomial over each term of the second binomial using the FOIL method.
  • Step 2: Combine like terms to express the function in standard quadratic form.

Now, let's expand the expression:
1. Multiply the first terms: 2xx=2x2 2x \cdot x = 2x^2
2. Multiply the outer terms: 2x(2)=4x 2x \cdot (-2) = -4x
3. Multiply the inner terms: 1x=x 1 \cdot x = x
4. Multiply the last terms: 1(2)=2 1 \cdot (-2) = -2

Next, we combine these results:
- The 2x2 2x^2 term remains as is.
- Add the linear terms: 4x+x=3x -4x + x = -3x
- The constant term is 2-2.

Thus, the expanded and simplified form of the function is:
f(x)=2x23x2 f(x) = 2x^2 - 3x - 2

The final expression in standard form is f(x)=2x23x2 f(x) = 2x^2 - 3x - 2 .

Answer

f(x)=2x23x2 f(x)=2x^2-3x-2

Exercise #8

Find the standard representation of the following function

f(x)=(x+3)(x4) f(x)=(x+3)(-x-4)

Video Solution

Step-by-Step Solution

To find the standard form of the given quadratic function f(x)=(x+3)(x4) f(x) = (x+3)(-x-4) , we will expand it using the distributive property.

Step 1: Expand the product.
Using the distributive property (or FOIL method):

f(x)=(x+3)(x4) f(x) = (x+3)(-x-4)

Apply distribution:
First: xx=x2 x \cdot -x = -x^2
Outside: x4=4x x \cdot -4 = -4x
Inside: 3x=3x 3 \cdot -x = -3x
Last: 34=12 3 \cdot -4 = -12

Step 2: Combine all terms together:

f(x)=x24x3x12 f(x) = -x^2 - 4x - 3x - 12

Step 3: Simplify by combining like terms:
Combine the x x terms:

f(x)=x27x12 f(x) = -x^2 - 7x - 12

Therefore, the standard representation of the function is f(x)=x27x12 f(x) = -x^2 - 7x - 12 .

The correct choice from the given options is choice 4.

f(x)=x27x12 f(x)=-x^2-7x-12

Answer

f(x)=x27x12 f(x)=-x^2-7x-12

Exercise #9

Find the representation of the product of the following function

f(x)=x27x+12 f(x)=x^2-7x+12

Video Solution

Step-by-Step Solution

To solve the problem of finding the product (factored) representation of the quadratic function f(x)=x27x+12 f(x) = x^2 - 7x + 12 , we proceed as follows:

  • Step 1: Identify the function, which is f(x)=x27x+12 f(x) = x^2 - 7x + 12 .
  • Step 2: We need to factor this quadratic expression. We're looking for two numbers whose product is 12 and whose sum is -7.
  • Step 3: The factor pairs of 12 are (1,12)(1, 12), (2,6)(2, 6), (3,4)(3, 4), including negative pairs because the sum must be negative.
  • Step 4: Consider the pair (3,4)(-3, -4). The product (3)×(4)(-3) \times (-4) equals 12, and the sum (3)+(4)(-3) + (-4) equals -7.

Therefore, the factors of the quadratic expression are x3 x - 3 and x4 x - 4 . This implies that the function f(x) f(x) can be expressed in product form as:

f(x)=(x3)(x4) f(x) = (x - 3)(x - 4)

This means the correct factorization is (x3)(x4)(x - 3)(x - 4), which corresponds to choice 3 from the given options.

Thus, the representation of the product of the function is (x3)(x4) (x - 3)(x - 4) .

Answer

(x3)(x4) (x-3)(x-4)

Exercise #10

Find the representation of the product of the following function

f(x)=x22x3 f(x)=x^2-2x-3

Video Solution

Step-by-Step Solution

The problem requires finding the product representation of the quadratic function f(x)=x22x3 f(x) = x^2 - 2x - 3 .

Let's execute the factorization of the quadratic equation:

  • The standard form for the function is f(x)=ax2+bx+c f(x) = ax^2 + bx + c . Here, a=1 a = 1 , b=2 b = -2 , c=3 c = -3 .
  • We seek two numbers that multiply to c=3 c = -3 and sum to b=2 b = -2 .
  • Checking possible integer pairs: (3,1)(-3, 1) can accomplish this, since 3×1=3-3 \times 1 = -3 and 3+1=2-3 + 1 = -2.
  • The factorization becomes f(x)=(x3)(x+1) f(x) = (x - 3)(x + 1) .

To verify, we can expand the binomials:

(x3)(x+1)=x2+x3x3=x22x3(x - 3)(x + 1) = x^2 + x - 3x - 3 = x^2 - 2x - 3.

This matches the original polynomial, confirming the product representation is correct.

In conclusion, the factorization or product representation of the given quadratic function is (x3)(x+1)\mathbf{(x-3)(x+1)}.

Answer

(x3)(x+1) (x-3)(x+1)

Exercise #11

Find the representation of the product of the following function

f(x)=x23x18 f(x)=x^2-3x-18

Video Solution

Step-by-Step Solution

To solve the problem of factoring the quadratic expression f(x)=x23x18 f(x) = x^2 - 3x - 18 , we will use the following method:

  • Step 1: Identify and understand the quadratic expression, which is given in standard form: ax2+bx+c ax^2 + bx + c . For this expression, a=1 a = 1 , b=3 b = -3 , and c=18 c = -18 .
  • Step 2: Compute the product of a a and c c , which yields 1(18)=18 1 \cdot (-18) = -18 . We need to find two numbers whose product is 18-18 and whose sum is 3-3.
  • Step 3: Look for pairs of factors of 18-18: - 1,181, -18 - 1,18-1, 18 - 2,92, -9 - 2,9-2, 9 - 3,63, -6 - 3,6-3, 6
  • Among these, the pair (3,6) (3, -6) adds up to 3-3 and multiplies to 18-18.

  • Step 4: Rewrite the quadratic expression using these numbers to represent the middle term:
    x23x18=x2+3x6x18 x^2 - 3x - 18 = x^2 + 3x - 6x - 18 .
  • Step 5: Group the terms to facilitate factoring:
    (x2+3x)+(6x18) (x^2 + 3x) + (-6x - 18) .
  • Step 6: Factor out the common factors in each grouped terms:
    x(x+3)6(x+3) x(x + 3) - 6(x + 3) .
  • Step 7: Factor out the common binomial:
    (x6)(x+3)(x - 6)(x + 3).

Therefore, the factorized form of the quadratic function f(x)=x23x18 f(x) = x^2 - 3x - 18 is (x6)(x+3) (x - 6)(x + 3) .

Answer

(x6)(x+3) (x-6)(x+3)

Exercise #12

Find the representation of the product of the following function

f(x)=x2+x2 f(x)=x^2+x-2

Video Solution

Step-by-Step Solution

To determine the product representation of f(x)=x2+x2 f(x) = x^2 + x - 2 , we can factor the quadratic equation by following these steps:

  • Step 1: Identify the product ac=1×(2)=2 ac = 1 \times (-2) = -2 and sum b=1 b = 1 .
  • Step 2: Find two numbers that multiply to 2-2 and add to 11. These numbers are 22 and 1-1.
  • Step 3: Rewrite the middle term using these numbers: x2+2x1x2 x^2 + 2x - 1x - 2 .
  • Step 4: Factor by grouping:
    - Group x2+2x x^2 + 2x and 1x2-1x - 2 as separate pairs:
    - x(x+2)1(x+2) x(x + 2) - 1(x + 2) .
  • Step 5: Factor out the common terms:
    (x+2)(x1)(x + 2)(x - 1).

Thus, the product representation of the function is (x+2)(x1) (x + 2)(x - 1) .

Answer

(x+2)(x1) (x+2)(x-1)

Exercise #13

Determine the points of intersection of the function

y=(x3)(x+3) y=(x-3)(x+3)

With the X

Video Solution

Step-by-Step Solution

To determine the points of intersection of the function y=(x3)(x+3) y=(x-3)(x+3) with the x-axis, we need to set y y to zero and solve for x x .

Follow these steps:

  • Step 1: Set the function equal to zero: (x3)(x+3)=0 (x-3)(x+3) = 0 .
  • Step 2: Apply the zero-product property, solving each factor for zero:
    • For x3=0 x-3=0 :
    • x=3 x = 3
    • For x+3=0 x+3=0 :
    • x=3 x = -3

Thus, the points of intersection of the function with the x-axis, or the x-intercepts, are (3,0)(-3, 0) and (3,0)(3, 0).

Therefore, the solution to the problem, confirming x-intercepts, is (3,0),(3,0)(-3, 0), (3, 0).

Answer

(3,0),(3,0) (-3,0),(3,0)

Exercise #14

Determine the points of intersection of the function

y=(x5)(x+5) y=(x-5)(x+5)

With the X

Video Solution

Step-by-Step Solution

In order to find the point of the intersection with the X-axis, we first need to establish that Y=0.

 

0 = (x-5)(x+5)

When we have an equation of this type, we know that one of these parentheses must be equal to 0, so we begin by checking the possible options.

x-5 = 0
x = 5

 

x+5 = 0
x = -5

That is, we have two points of intersection with the x-axis, when we discover their x points, and the y point is already known to us (0, as we placed it):

(5,0)(-5,0)

This is the solution!

Answer

(5,0),(5,0) (5,0),(-5,0)

Exercise #15

Determine the points of intersection of the function

y=x(x+5) y=x(x+5)

With the X

Video Solution

Step-by-Step Solution

To determine the points of intersection with the x-axis for the function y=x(x+5) y = x(x+5) , follow these steps:

  • Step 1: Set the function equal to zero to find the x-intercepts: y=0 y = 0 .
  • Step 2: Solve the equation x(x+5)=0 x(x+5) = 0 .

Considering the product x(x+5)=0 x(x+5) = 0 :

  • If x=0 x = 0 , then one solution is x=0 x = 0 .
  • If x+5=0 x+5 = 0 , then solving for x x gives x=5 x = -5 .

Thus, the two points of intersection with the x-axis are:

(5,0)(-5, 0) and (0,0)(0, 0).

Therefore, the points of intersection of the function y=x(x+5) y = x(x+5) with the x-axis are (5,0)(-5, 0) and (0,0)(0, 0).

Answer

(5,0),(0,0) (-5,0),(0,0)