If (gog)(x)=64x-81, it's domain is (???, infinity)

Question

Please help me find the domain. Given that f (x)=1/x & g (x)=8x-9. 

Answer 1

FIRST, YOU SHOULD ASK FOR its DOMAIN--THE CONTRACTION "IT'S" IS USED only TO MEAN "IT IS"

 

(gog)(x) = 8(8x-9) - 9 ... you got that right. 

 

Its domain is all Reals.  I.e. (-infinity,infinity)  No domain restrictions on polynomials!