Question

let f(x)=x/x-4. find a function y=g(x) so that (fog)(x)=x (f round g) any help?

Answer 1

just diffrentiate it

Answer 2

how? i am new at this round thing... can u give me an ex?

Answer 3

Let \(f(x)=x+1\) and \(g(x)=x^2\).
\(fog(x)=f(g(x))\).
To find \(fog(x)\)
put g(x) in place of x in f(x).
That is
\(f(g(x))=(g(x))+1\)
\(=x^2+1\)
Getting it @aboulmich2?

Answer 4

yes

Answer 5

yes this i got it but in reverse if i have only f(x) how can i find g(x)?

Answer 6

i mean how to solve the question i wrote in details plzz

Answer 7

f(x)=x/x-4 and ur g(x)=y.
To find f(g(x))
u wil put g(x) in place of x in f(x) right?

Answer 8

right

Answer 9

f(g(x))=y/y-4
Also u r given that f(g(x))=x.
So
x=y/y-4
Nw solve for y to find g(x)

Answer 10

okayy i got it now thanks everyone

Answer 11

yw:)