Question

PLEASR HELP!!!! Evaluate this piecewise function at x=2 and x=4.

Answer 1

Answer:

Option D.

Step-by-step explanation:

Consider the given piecewise function

$f(x)=\begin{cases}3x & \text{ if } x\neq 4 \\ -2x & \text{ if } x=4 \end{cases}$

For x ≠ 4

$f(x)=3x$

For x=4,

$f(x)=-2x$

The value of function at x=2 is

$f(2)=3(2)=6$

The value of function at x=4 is

$f(x)=-2(4)=-8$

Since f(2)=6 and f(4)=-8, therefore the correct option is D.

Answer 2

You can see the side conditions for the function. We read the x CANNOT be 4. See it?

We evaluate the bottom piece at x = 4. Let's do that.

f(x) = -2x

Let x be 4.

f(4) = -2(4)

f(4) = -8

What about the other piece?

Evaluate the top piece at x = 2.

Let's do that.

f(x) = 3x

Let x be 2.

f(2) = 3(2)

f(2) = 6

Answer: Choice D

Did you follow? It is a piecewise function. Solve it one piece at a time keeping each side condition in mind along the way.