Question 685001
f(g(x)) = {{{3(x/3+2)-6}}}
= {{{3(x/3) + 3(2) - 6}}}
f(g(x))= x
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g(f(x)) = {{{(3x-6)/3 + 2}}}
= {{{3x/3 - 6/3 + 2}}}
g(f(x)) = x
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f(x) = 3x - 6
y = 3x - 6
y + 6 = 3x
x = {{{(y+6)/3}}}
{{{f^-1(x) = x/3 + 2}}}
so g(x)  is an inverse function of f(x)
and
g(x) = {{{x/3 + 2}}}
y = {{{x/3 + 2}}}
y - 2 = {{{x/3}}}
x = 3(y-2)
{{{g^-1(x) = 3x - 6)}}}
so f(x) is an inverse function of g(x)
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