Let f(x) = x^2 + 7 and

Question

g(x) = x-3/x
Find the composition
of (fºg)(-3)

Not necessarily looking for the answer but i don’t understand how to set up the question

Answer 1

replace the x in f(x) with g(x)
(x-3/x)^2 + 7 or did you mean ((x-3)/x)^2 + 7

Replace with 3
The first way would be the second way would be
-3 minus 3/-3 (-3-3)/-3 = -6/-3 or 2 squared = 4
-3-1 = -4 squared 4 + 7 = 11
16+ 7 = 23

Answer 2

(f º g) means that g(x) becomes the variable for f(x)

this is also written as ... f[g(x)] ... which might make it a little clearer

if ... f(x) = 2x + 1 ... and ... g(x) = 4x^2 ... then ... (f º g)(x) = 2(4x^2) + 1