SOLUTION: Let g(x) = 2x and h(x) = {{{ x^2 + 4 }}}. Question: (g o h)(-2) I will like to know if I am doing this question correctly because I do not know if I am plugging the -2 in the c

Algebra ->  Functions -> SOLUTION: Let g(x) = 2x and h(x) = {{{ x^2 + 4 }}}. Question: (g o h)(-2) I will like to know if I am doing this question correctly because I do not know if I am plugging the -2 in the c      Log On


   

Question 837984: Let g(x) = 2x and h(x) = +x%5E2+%2B+4+.
Question: (g o h)(-2)
I will like to know if I am doing this question correctly because I do not know if I am plugging the -2 in the correct place.
g(h(-2))= 2x
I've been plugging -2 in for the h(x)= +x%5E2+%2B+4+.
h(-2)= +%28-2%29%5E2+%2B+4+
4+4
8
Then plugging in the answer for the g(x) as the x value
g(8)=2x
2(8)
16
Am I doing this problem correctly or solving it the wrong way?
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Form the composition, and then plug-in x=-2; maybe easier.
g%28x%29=2x, and h%28x%29=x%5E2%2B4.
-
g%28h%28x%29%29=2%28x%5E2%2B4%29=2x%5E2%2B8
Let x=-2.
g%28h%28-2%29%29=2%28-2%29%5E2%2B8
g%28h%28-2%29%29=8%2B8=16
-
I did not check your work too carefully, but you showed the same result.