Question 355823
HI,
You are absolutely correct (f 0 g)(x) means for every x in the f(x) function, g(x) has been substituted for it.
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f(x)=2x &  h(x)= 4
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(note put the '4' in place of the x in the f(x) function)
(f o h)(x)= 2(4) = 8   
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(f o g)(4), let f(x)=3x-2 and g(x)=x^2+x 
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substitute x^2+x for x in the (3x-2) expresion
(f o g)(4) = (3(x^2+x)-2 
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solve for x = 4
(f o g)(4) = 3*(20)-2 = 58