The most basic quadratic function a=−1,b=0,c=0 Maximum, sad face function, its vertex is (0,0) The axis of symmetry of this function is X=0. The interval of increase of the function: X<0 The interval of decrease of the function: X>0 Set of positivity: None. The entire parabola is below the axisX. Set of negativity: All X except for X=0
y=ax2
Properties of the function: The quadratic function anynumber=a,b=0,c=0
Its vertex is (0,0) The axis of symmetry of this function is X=0.
As a increases, the parabola will have a smaller opening - closer to its axis of symmetry. As a 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
of the point 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 into the equation.
Step 2: Perform the calculation to find y.
Now, let's work through each step:
Step 1: The given equation is y=x2. We need to substitute x=2 into this equation.
Step 2: Substitute to get y=(2)2. Calculate 2×2=4.
Therefore, the value of y when x=2 is y=4.
Hence, the solution to the problem is y=4.
Answer
y=4
Exercise #2
Complete:
The missing value of the function point:
f(x)=x2
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.
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. We know f(?)=16, so we can write:
x2=16
Step 2: To solve for x, we take the square root of both sides of the equation:
x=±16
Step 3: Solve for 16:
The square root of 16 is 4, so:
x=4 or x=−4
This gives us the two solutions: x=4 and x=−4.
Step 4: Compare these solutions to the answer choices. The correct choice is:
f(4) and f(−4)
Therefore, the solution to the problem is f(4) and f(−4).
Answer
f(4)f(−4)
Exercise #3
What is the value of y for the function?
y=x2
of the point 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.
Step 2: Substitute the given x value into the function.
Step 3: Calculate the resulting value for y.
Now, let's work through each step:
Step 1: The problem states that x=6.
Step 2: Using the function y=x2, we substitute x=6.
Step 3: Perform the calculation: y=62.
Calculating 62, we get 36.
Therefore, for the function y=x2, when x=6, the value of y is y=36.
Answer
y=36
Exercise #4
Complete:
The missing value of the function point:
f(x)=x2
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 for f(?)=25.
Step 2: Solve for x by applying the square root operation.
Now, let's work through each step:
Step 1: We start with the equation x2=25 derived from f(x)=25.
Step 2: To solve for x, we take the square root of both sides:
x=±25
Calculating the square root gives us x=±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.
Concluding, the missing value of the function point is f(5), which coincides with choice 1.
Answer
f(5)
Exercise #5
Complete:
The missing value of the function point:
f(x)=x2
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.
Step 2: Solve for 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.
Step 2: Solving for x, we take the square root of both sides: x=±9.
Step 3: This yields two solutions: x=3 and x=−3.
Comparing these values with the given choices:
Choice 1: f(3) corresponds to x=3.
Choice 3: f(−3) corresponds to x=−3.
Both choices f(3) and f(−3) are correct, leading us to select the combined choice: Answer A+C.
Answer
Answer A+C
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