SOLUTION: Let f(x)=x^2+4, and g(x)=x-1 Compute (g 0 f)(x), (f 0 G)(x)

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Question 52349: Let f(x)=x^2+4, and g(x)=x-1 Compute (g 0 f)(x), (f 0 G)(x)
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=x^2+4
g(x)=x-1
(gof)(x) means you substitute the function of f into the function of g where x is.
(gof)(x)=g(f(x))=g(x^2+4)
g(x^2+4)=(x^2+4)-1
=x^2+4-1
=x^2+3
(fog)(x) means you substitute the function of g into the function of f where x is.
(fog)(x)=f(g(x))=f(x-1)
f(x-1)=(x-1)^2+4
=(x^2-2x+1)+4
=x^2-2x+1+4
=x^2-2x+5