Question

Evaluating the function f(x) = 2x^2 + 3x - 1 at x = -4

Answer 1

To evaluate the function \( f(x) = 2x^2 + 3x - 1 \) at \( x = -4 \), we substitute \(-4\) into the function:

\[
f(-4) = 2(-4)^2 + 3(-4) - 1
\]

Calculating each term step by step:

1. Calculate \((-4)^2\):
\[
(-4)^2 = 16
\]

2. Multiply by 2:
\[
2 \cdot 16 = 32
\]

3. Calculate \(3(-4)\):
\[
3 \cdot (-4) = -12
\]

4. Now, combine all the terms:
\[
f(-4) = 32 - 12 - 1
\]

5. Perform the addition and subtraction:
\[
f(-4) = 32 - 12 = 20
\]
\[
f(-4) = 20 - 1 = 19
\]

Therefore, \( f(-4) = 19 \).