Let f(x) = 3x - 4 and g(x) = x^2 - 2, what is the value of f(g(2)) and f(g(x))?

1 Answer
Mar 4, 2016

color(blue)(f(g(2))=2)
color(white)(.)
color(blue)(g(f(x))= -15x+14)

Explanation:

Assuming you mean:
f(x)=3x-4
g(x)=x^2-2
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(blue)("To determine "f(g(2)))

g(2)=2^2-2" " =" "4-2" "=" "2

f(g(2))=3(2)-4" " =" "6-4" "=" "2

color(blue)(f(g(2))=2)

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(blue)("To determine "g(f(x)))

Given that f(x)=3x-4 then

g(f(x))= (3x-4)^2-2

g(f(x))= (9x-24x+16)-2

color(blue)(g(f(x))= -15x+14)