f of g stuff help!!!?

2 ⤊

if (x) = 5x+7 and g(f(x)) = (5x+7)^2 what is g(x)

2007-05-21 19:17:56 · 5 answers · asked by bransred 1 in Science & Mathematics ➔ Mathematics

f(x) = 5x+7
g(f(x)) = (5x+7)^2
g(f(x)) = (f(x))^2
g(x) = x^2

2007-05-21 19:20:51 · answer #1 · answered by Anonymous · 2⤊ 0⤋

g(x) = x^2

2007-05-22 02:38:19 · answer #2 · answered by Anonymous · 0⤊ 0⤋

Take f(x) = y
so .. 5x + 7 = y
or x = (y - 7)/5

now, g(f(x)) = (5x+7)^2
do the above substitution, we get
g(y) = y^2

so we have
g(x) = x^2

2007-05-22 02:23:36 · answer #3 · answered by ? 3 · 0⤊ 0⤋

f(x) = 5x+7 , so g(f(x))= g(5x+7)=(5x+7)^2
So g(x) = x^2

2007-05-22 03:54:47 · answer #4 · answered by sothanaphan 2 · 0⤊ 0⤋

g(x) = xÂ²

HTH

Doug

2007-05-22 02:33:59 · answer #5 · answered by doug_donaghue 7 · 0⤊ 0⤋