Question

Given the function f(x) = 20x² - 18 - 25, find f(-1).

Answer 1

f(-1) for the function f(x) = 20x² - 18 - 25, is f(-1) = -23.

Step-by-step explanation:

To find f(-1) for the given function, f(x) = 20x² - 18 - 25, substitute x with -1 in the function:

f(-1) = 20(-1)² - 18 - 25

First, calculate (-1)²:

-1 ² = 1

Next, multiply this value by 20:

20 × 1 = 20

Now, subtract 18 and then 25 from this result:

20 - 18 = 2

2 - 25 = -23

Therefore, f(-1) = -23.