Question

What is the value of f(-4) in the piecewise function f(x)= -x-5 for -5<= x <= -2; -x^2+1 for -2<=x<=2; (x-3)^2+2 for 2<=x<=4? If that makes any since

Answer 1

We first need to pick the correct piece to use. In this case, we will use f(x) = -x-5 because -5<=-4.

Then, we use direct substitution:
f(-4) = -(-4) - 5
f(-4) = -1

Answer 2

The value for f(-4) in the piecewise function is -1

Explanation:

As the function is defined by pieces we must choose the correct interval when replacing. In this case, the value of the function needs to be calculated in x=4.

This value of x is within the interval:

-5<=x<=-2

Therefore we replaced in the corresponding expression:

f(x)=-x-5

f(-4)=-(-4)-5=-1

Take into account this case is not particularly a function since, for example, in the value of x=-2 the expression can take two values corresponding to two different pieces. The obtained result is only valid in the range for -5<=x<=-2.