Question #658c3

1 Answer
Sep 10, 2016

Start inside the expression by finding #g# "of" -1 or #g(-1)#

Substitute #-1# for #x# in #g(x)#.
#g(-1)= (-1)^2-7(-1)-9 = -1#

Now look at the "outside" part of the expression# f# "of" #g(-1)#.

We just found #g(-1)= -1#.
BTW, that's a coincidence that both #x=-1# and #g(-1)= -1#.

Substitute #g(-1)# in for #x# in #f(x)=x-2#.

#f(g(-1)) = f(-1)= -1-2=-3#

I'm not sure why you've listed the numbers -21, -3, 3, and 21, but if you have to find#f(g(x))# for these values, just follow the same process.