The functions (y=x2,y=x2,y=ax2)(y=x^2,y=-x^2,y=ax^2 )

Y=X2Y=X^2
A- The basic functions   Y=X²

Properties of the function:

The most basic quadratic function b=0b=0,c=0c=0
Minimum, happy face function, its vertex is (0,0)(0,0)
The axis of symmetry of this function is X=0X=0.
The function's interval of increase: X>0X>0
The function's interval of decrease: X<0X<0
Set of positivity: Every XX except 00.
Set of negativity: None. The entire parabola is above the axisXX.

Practice Parabola of the form y=x²

Examples with solutions for Parabola of the form y=x²

Exercise #1

What is the value of y for the function?

y=x2 y=x^2

of the point x=2 x=2 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Substitute the given value of x x into the equation.
  • Step 2: Perform the calculation to find y y .

Now, let's work through each step:
Step 1: The given equation is y=x2 y = x^2 . We need to substitute x=2 x = 2 into this equation.

Step 2: Substitute to get y=(2)2 y = (2)^2 . Calculate 2×2=4 2 \times 2 = 4 .

Therefore, the value of y y when x=2 x = 2 is y=4 y = 4 .

Hence, the solution to the problem is y=4 y = 4 .

Answer

y=4 y=4

Exercise #2

Complete:

The missing value of the function point:

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

f(?)=16 f(?)=16

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Set up the equation from the function definition.
  • Step 2: Solve the equation by taking the square root of both sides.
  • Step 3: Identify all possible values for x x .
  • Step 4: Compare with the given answer choices.

Now, let's work through each step:

Step 1: We start with the equation given by the function f(x)=x2 f(x) = x^2 . We know f(?)=16 f(?) = 16 , so we can write:

x2=16 x^2 = 16

Step 2: To solve for x x , we take the square root of both sides of the equation:

x=±16 x = \pm \sqrt{16}

Step 3: Solve for 16 \sqrt{16} :

The square root of 16 is 4, so:

x=4 x = 4 or x=4 x = -4

This gives us the two solutions: x=4 x = 4 and x=4 x = -4 .

Step 4: Compare these solutions to the answer choices. The correct choice is:

f(4) f(4) and f(4) f(-4)

Therefore, the solution to the problem is f(4) f(4) and f(4) f(-4) .

Answer

f(4) f(4) f(4) f(-4)

Exercise #3

What is the value of X for the function?

y=x2 y=x^2

of the point y=4 y=4 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Set the equation of the function with the given point, x2=4 x^2 = 4 .
  • Step 2: Solve for x x by taking the square root of both sides. This accounts for both the positive and negative solutions.
  • Step 3: Evaluate the expression to find the solutions.

Now, let's work through each step:
Step 1: Set up the equation based on the given information:
We have x2=4 x^2 = 4 .

Step 2: Solve by taking the square root of both sides:
Taking the square root, we get x=±4 x = \pm\sqrt{4} .

Step 3: Simplify to find the values of x x :
The square root of 4 is 2, thus x=2 x = 2 and x=2 x = -2 .

Therefore, the solutions for x x are x=2 x = 2 and x=2 x = -2 .

The correct answer is choice Answers a + b, which corresponds to having solutions x=2 x = 2 and x=2 x = -2 .

Answer

Answers a + b

Exercise #4

What is the value of X for the function?

y=x2 y=x^2

of the point y=16 y=16 ?

Video Solution

Step-by-Step Solution

To solve this problem, let's find the steps required to determine x x when y=16 y = 16 in the function y=x2 y = x^2 :

  • Step 1: Substitute the given y y into the equation to get x2=16 x^2 = 16 .
  • Step 2: To solve x2=16 x^2 = 16 , take the square root of both sides, remembering to include both positive and negative roots. This yields x=±16 x = \pm\sqrt{16} .
  • Step 3: Simplify to find x=±4 x = \pm4 , which gives the solutions x=4 x = 4 and x=4 x = -4 .

Thus, the value(s) of x x that satisfy y=16 y = 16 in the function y=x2 y = x^2 are x=4 x = 4 and x=4 x = -4 .

Therefore, the solution to the given problem is x=4,x=4 x = 4, x = -4 .

Answer

x=4,x=4 x=4,x=-4

Exercise #5

What is the value of X for the function?

y=x2 y=x^2

of the point y=36 y=36 ?

Video Solution

Step-by-Step Solution

To solve the problem, we will proceed with the following steps:

  • Identify the provided equation and condition.
  • Apply the square root property to solve the equation.
  • Verify the solution with the given choices.

Step-by-step solution:

Step 1: Substitute y=36 y = 36 into the equation y=x2 y = x^2 , which gives:

x2=36 x^2 = 36

Step 2: Solve for x x by taking the square root of both sides. Using the square root property, we have:

x=±36 x = \pm \sqrt{36}

Since the square root of 36 is 6, we find that:

x=±6 x = \pm 6

Therefore, the solutions to the equation are x=6 x = 6 and x=6 x = -6 .

Thus, the value of x x for y=36 y = 36 in the function y=x2 y = x^2 is x=±6 x = \pm 6 .

Answer

x=±6 x=\pm6

Exercise #6

What is the value of y for the function?

y=x2 y=x^2

of the point x=6 x=6 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the value given for x x .
  • Step 2: Substitute the given x x value into the function.
  • Step 3: Calculate the resulting value for y y .

Now, let's work through each step:
Step 1: The problem states that x=6 x = 6 .
Step 2: Using the function y=x2 y = x^2 , we substitute x=6 x = 6 .
Step 3: Perform the calculation: y=62 y = 6^2 .

Calculating 62 6^2 , we get 36 36 .
Therefore, for the function y=x2 y = x^2 , when x=6 x = 6 , the value of y y is y=36 y = 36 .

Answer

y=36 y=36

Exercise #7

Given the function:

y=x2 y=x^2

Is there a point for ? y=16 y=16 ?

Video Solution

Step-by-Step Solution

The problem asks us to find an x x such that in the function y=x2 y = x^2 , the value of y y becomes 16. To do this, we'll substitute y=16 y = 16 into the equation and solve for x x .

1. Start with the equation of the function:

y=x2 y = x^2

2. Substitute y=16 y = 16 into the equation:

16=x2 16 = x^2

3. Solve x2=16 x^2 = 16 for x x :

  • Take the square root of both sides to solve for x x :
  • x=±16 x = \pm \sqrt{16}
  • This gives x=4 x = 4 or x=4 x = -4

4. Identify the points on the function for these values of x x :

  • For x=4 x = 4 , the point is (4,16)(4, 16).
  • For x=4 x = -4 , the point is (4,16)(-4, 16), but this is not provided in the choice list.

Among the given options, the point we find in the choices is:

(4,16) (4, 16)

Therefore, the correct answer is the choice that corresponds with this point:

(4,16) (4,16)

Answer

(4,16) (4,16)

Exercise #8

Given the function:

y=x2 y=x^2

Is there a point for ? y=4 y=4 ?

Video Solution

Step-by-Step Solution

To determine if there is a point on the graph of the parabola y=x2 y = x^2 where y=4 y = 4 , we need to find values of x x that satisfy the equation x2=4 x^2 = 4 .

Let's solve the equation step by step:

  • Set the equation: x2=4 x^2 = 4 .
  • Take the square root of both sides to solve for x x :
  • x=4 x = \sqrt{4} or x=4 x = -\sqrt{4} .
  • This gives us x=2 x = 2 or x=2 x = -2 .

Therefore, the points on the graph where y=4 y = 4 are (2,4) (2, 4) and (2,4)(-2, 4) .

This matches the provided correct answer of (2,4) (2, 4) and (2,4)(-2, 4) .

Therefore, the correct solution is the point set (2,4) (2, 4) and (2,4)(-2, 4) .

Answer

(2,4) (2,4) (2,4) (-2,4)

Exercise #9

Does the function y=x2 y=x^2 pass through the point where y = 36 and x = 6?

Video Solution

Step-by-Step Solution

To determine if the function y=x2 y = x^2 passes through the point (6,36) (6, 36) , follow these steps:

  • Step 1: Identify the given point and function. We have x=6 x = 6 and we need to check if y=36 y = 36 when y=x2 y = x^2 .
  • Step 2: Substitute x=6 x = 6 in the function y=x2 y = x^2 :
    y=62=36 y = 6^2 = 36 .
  • Step 3: Compare the calculated y y value (36) to the given value (36).

Since the calculated value of y y is equal to the given value, the function y=x2 y = x^2 indeed passes through the point (6,36) (6, 36) .

Therefore, the answer is Yes.

Answer

Yes

Exercise #10

Given the function:

y=x2 y=x^2

Is there a point for ? y=6 y=-6 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the given function and required y-value.
  • Step 2: Attempt to solve x2=6 x^2 = -6 for x x .
  • Step 3: Conclude based on the results of the equation.

Let's work through each step:

Step 1: The function we are dealing with is y=x2 y = x^2 , and we need to find x x such that y=6 y = -6 .

Step 2: Substitute 6-6 for y y, which gives us:

x2=6 x^2 = -6

Step 3: To solve x2=6 x^2 = -6 , consider whether it is possible for a real number squared to equal a negative number. A critical point here is that the square of any real number is non-negative. Therefore, there is no real value of x x that satisfies x2=6 x^2 = -6 .

Thus, there is no point where y=6 y = -6 for the function y=x2 y = x^2 .

The correct answer is No.

Answer

No

Exercise #11

Given the function:

y=x2 y=x^2

Is there a point for ? y=2 y=-2 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Analyze the equation y=x2 y = x^2 .
  • Step 2: Investigate whether a negative y y -value is possible.

Now, let's work through each step:
Step 1: The function we have is y=x2 y = x^2 . This function is defined for all real numbers and always gives a non-negative value y y because squaring a real number cannot result in a negative number.

Step 2: We need to check whether y=2 y = -2 is possible by solving x2=2 x^2 = -2 . In the real number system, no real number x x satisfies this equation since the square of any real number is non-negative.
Therefore, there is no real point where y=2 y = -2 on the graph of the function y=x2 y = x^2 .

Therefore, the solution to the problem is No.

Answer

No

Exercise #12

Complete:

The missing value of the function point:

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

f(?)=9 f(?)=9

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Set up the equation x2=9 x^2 = 9 .
  • Step 2: Solve for x x by taking the square root of both sides.
  • Step 3: Choose the correct answer from the given options.

Now, let's work through each step:
Step 1: We set x2=9 x^2 = 9 .
Step 2: Solving for x x , we take the square root of both sides: x=±9 x = \pm \sqrt{9} .
Step 3: This yields two solutions: x=3 x = 3 and x=3 x = -3 .

Comparing these values with the given choices:

  • Choice 1: f(3) f(3) corresponds to x=3 x = 3 .
  • Choice 3: f(3) f(-3) corresponds to x=3 x = -3 .

Both choices f(3) f(3) and f(3) f(-3) are correct, leading us to select the combined choice: Answer A+C.

Answer

Answer A+C

Exercise #13

Complete:

The missing value of the function point:

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

f(?)=25 f(?)=25

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Set up the equation based on the function f(x)=x2 f(x)=x^2 for f(?)=25 f(?)=25 .
  • Step 2: Solve for x x by applying the square root operation.

Now, let's work through each step:
Step 1: We start with the equation x2=25 x^2 = 25 derived from f(x)=25 f(x) = 25 .
Step 2: To solve for x x , we take the square root of both sides:

x=±25 x = \pm \sqrt{25}

Calculating the square root gives us x=±5 x = \pm 5 . However, we are looking for a specific point that fits one of the answer choices:
Therefore, the solution based on the choices provided is x=5 x = 5 .

Concluding, the missing value of the function point is f(5) f(5) , which coincides with choice 1.

Answer

f(5) f(5)

Exercise #14

What is the value of X for the function?

y=x2 y=x^2

of the point y=25 y=25 ?

Video Solution

Step-by-Step Solution

Let's solve the problem by following these steps:

  • Step 1: Identify the equation to solve.
  • Step 2: Apply the square root to both sides of the equation.
  • Step 3: Solve for both positive and negative values of x x .

Step 1: We start with the equation derived from the function:
x2=25 x^2 = 25

Step 2: To isolate x x , we take the square root of both sides. Remember, the square root of a number can be both positive and negative:
x=±25 x = \pm \sqrt{25}

Step 3: Simplify the square root:
x=±5 x = \pm 5 , which means x=5 x = 5 or x=5 x = -5

Therefore, the values of x x that satisfy y=25 y = 25 in the function y=x2 y = x^2 are x=5 x = 5 and x=5 x = -5 .

Looking at the choices given, the correct answer is:

x=5,x=5 x=5,x=-5

Answer

x=5,x=5 x=5,x=-5

Exercise #15

What is the value of X for the function?

y=x2 y=x^2

of the point y=8 y=8 ?

Video Solution

Step-by-Step Solution

The problem requires us to find the value of x x for the function y=x2 y = x^2 when y=8 y = 8 .

Let's solve this step-by-step:

  • Step 1: Set up the equation based on the given function:
     y=x2\ y = x^2 becomes  x2=8\ x^2 = 8 .
  • Step 2: Solve for x x by taking the square root of both sides:

Since  x2=8\ x^2 = 8 , we take the square root of both sides to find x x :

x=±8 x = \pm\sqrt{8}

Step 3: Simplify the square root:

The square root of 8 can be simplified to  8=4×2=42=22\ \sqrt{8} = \sqrt{4 \times 2} = \sqrt{4} \cdot \sqrt{2} = 2\sqrt{2} .

Thus,  x=±22\ x = \pm 2\sqrt{2} .

Therefore, the solution is x=±22 x = \pm 2\sqrt{2} , which corresponds to choice 4.

Answer

x=±22 x=\pm2\sqrt{2}