Question

F(x)=x^2+6 and G(x)=x+8\x find (g o f) (-7)

Answer 1

Problem:
Given,
f(x)= x^2+6
g(x) = (x+8)/x

Find: g(f(-7))

Solution:
In general,
(g o f)(x) = g(f(x))

In this case,
g(f(x)) = (x^2+6+8)/(x^2+6) = (x^2+14)/(x^2+6)

Therefore,
(g o f)(-7) = g(f(-7))
g(f(-7)) = ((-7)^2+14)/((-7)^2+6) = (49 + 14)/(49 + 6) = 63/55

Thus,
g(f(-7) = 63/55