Evaluating Functions

Front

What is a function?

Back

A function is a relation that assigns exactly one output for each input from a set of inputs.

Front

How do you evaluate a function at a specific point?

Back

To evaluate a function at a specific point, substitute the value of the variable into the function's equation.

Front

What does it mean to find f(-9) if f(x) = \frac{1}{2}(x + 5) - 3?

Back

It means to replace x with -9 in the function and simplify to find the output.

Front

Evaluate f(-9) for f(x) = \frac{1}{2}(x + 5) - 3.

Back

f(-9) = \frac{1}{2}(-9 + 5) - 3 = -5.

Front

What is the formula for g(x) = -2x^2 + 9?

Back

This is a quadratic function where the output decreases as x moves away from 0.

Front

Evaluate g(6) for g(x) = -2x^2 + 9.

Back

g(6) = -2(6^2) + 9 = -63.

Front

What is the first step to find f(1) if f(x) = 2x + 1?

Back

Plug a 1 in for all the x's.

Front

Evaluate f(1) for f(x) = 2x + 1.

Back

f(1) = 2(1) + 1 = 3.

Front

What does f(-4) represent in the function f(x) = 3x + 9?

Back

It represents the output of the function when the input is -4.

Front

Evaluate f(-4) for f(x) = 3x + 9.

Back

f(-4) = 3(-4) + 9 = -3.