Question

Find f(−1) given f(x)=−3x3+2x2+24
A. -23
B. 28
C. 29
D. 23

Answer 1

Answer:

C. 29

Step-by-step explanation:

$f(x) = -3x^3 + 2x^2 +24$

• To calculate $f(-1)$ , we have to replace x with -1 in the definition of $f(x)$ , and calculate the value:

$f(-1) = -3(-1)^3 + 2(-1)^2 + 24$

         ⇒ $-3(-1) +2(1) + 24$

         ⇒ $3 + 2 + 24$

         ⇒ $29$

Answer 2

$\huge\boxed{\textsf{C.}\ 29}$

We have this equation:

$f(x)=-3x^3+2x^2+24$

Substitute $x=-1$:

$f(-1)=-3(-1)^3+2(-1)^2+24$

Simplify to find the final answer:

$\begin{aligned}f(-1)&=-3(-1)+2(1)+24\\&=3+2+24\\&=5+24\\&=\boxed{29}\end{aligned}$