The functions y=x²

🏆Practice parabola of the form y=x²

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.

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Test yourself on parabola of the form y=x²!

einstein

What is the value of y for the function?

\( y=x^2 \)

of the point \( x=2 \)?

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y=x2y=-x^2
A1 - Basic functions Y=-X²

Properties of the Function

The most basic quadratic function a=1a=-1,b=0b=0 ,c=0c=0
Maximum, sad face function, its vertex is (0,0)(0,0)
The axis of symmetry of this function is X=0X=0.
The interval of increase of the function: X<0X<0
The interval of decrease of the function: X>0X>0
Set of positivity: None. The entire parabola is below the axisXX.
Set of negativity: All XX except for X=0X=0


y=ax2y=ax^2

A2 - Basic functions   Y=ax²

Properties of the function:
The quadratic function 
anynumber=aany number = a,b=0b=0,c=0c=0

Its vertex is (0,0)(0,0)
The axis of symmetry of this function is X=0X=0.

As aa  increases, the parabola will have a smaller opening - closer to its axis of symmetry.
As aa  decreases, the parabola will have a larger opening - further from its axis of symmetry. 


Examples and exercises with solutions for the functions 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

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