Given that f(x) = x^2-3 and g(x) = 2x+1, find each of the following, if it exists.

a. (fg)(-root3)

b. (gf)(-1/2)

3 answers

do you mean f(g(x)) ?

f(g(x))
= (g(x))^2 - 3
= (2x+1)^2 - 3

then (f(g(-√3))
= (-2√3 + 1)^2 - 3
= 12 - 4√3 + 1 - 3
= 10 - 4√3

do the other one the same way
remember this time you want
g(f(x))
= g(x^2-3)
= 2(x^2-3) + 1
The first one was (fg)(-root3). Does this answer your ? Thanks for the help!
What happend to the (-1/2) in the second problem?