Question 4498
f(x)=x^2+x and g(x)=2x+1
a)    (g o f)(x) = 2(x^2+x)+1 = 2x^2+2x+1
.
b)    (f o g)(x)= (2x+1)^2 + 2x+1 = 4x^2+4x+1 + 2x+1 = 4x^2+6x+2
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c)    (f+g)(2) = x^2+x +2x+1 = x^2 + 3x+1 = 2^2+ 3*2+1 =11
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d)    (f-g)(3) = x^2+x -2x-1 = x^2 -x-1 = 3^2-3-1= 5