Question

Please help! I cannot figure this out.

Answer 1

Answer: f(-2)=3

Explanation:

`f(x)=\left\{\begin{array}{ccc}-(x+1)^2+4\ for\ x < -1\\2\ \ \ \ for\ \ x=-1\\4\ \ \ for \ \ \ x > -1\end{array}\right`

`-2\in(-\infty,-1)\\Hence,`

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

Answer 2

well, for the piece-wise function, we'd like to know f(-2), or namely what is f(x) when x = -2?

well, f(x) is 2 for x = -1

f(x) is 4 for x > -1

keeping in mind that in the negative side of the number line, the closer to 0, the larger, thus -1 is much larger than -1,000, so hmmm -2 is farther from 0 than -1 is, so -1 is larger than -2, so when x = -2, x < -1, and the function that applies when x < -1 is -(x+1)² + 4, so then

`f(x)= \begin{cases} -(x+1)^2 + 4&\stackrel{-2}{x} < -1\\\\ 2&x=-1\\\\ 4&x > -1 \end{cases} \\\\\\ f(-2)\implies -(~~(-2)+1~~)^2 + 4\implies -(-1)^2+4\implies -(-1)(-1)+4 \\\\\\ -(1)+4\implies -1+4\implies \text{\LARGE 3}`