please solve this equation (if possible)?

let
f(x) = x /x+3 and g (x ) = x^2

find whether (f o g) (x) and (g o f ) (x) are equal or not ?

its really very very very urgent

Marcus C2007-10-17T10:45:33Z

Favorite Answer

they dont equal
(f o g) (x) = f(g(x)) = f(x) = g(x)/g(x) +3
= x^2/x^2 +3
(g o f ) (x) = g(f(x)) = g(x) = f(x)^2
= (x/(x+3))^2

mohanrao d2007-10-17T17:50:28Z

(f o g)(x) = f(g(x)) = f(x^2)

=> x^2/(x^2+3)

(g o f)(x) = g(f(x) = g(x/(x+3))

= [(x/x+3)]^2

= x^2/(x^2 + 9 +6x)

so (f o g) (x) and (g o f) (x) are not equal

Nima O2007-10-17T17:47:02Z

f(g(x)) = (x^2)/((x^2)+3)
g(f(x)) = (x/x+3)^2 = (x^2)/((x+3)^2)

So they are not equal!