SOLUTION: Given f(x)=3x^2+2x and g(x)=x-5 find (f*g)(3), (f-g)(5) and (f o g)(x).

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Question 22121: Given f(x)=3x^2+2x and g(x)=x-5 find (f*g)(3), (f-g)(5) and (f o g)(x).
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
f(3) = 3*3^2+2*3= 27+6 =33
g(3) = 3-5 = -2
(f*g)(3) = f(3)*g(3) = 33*(-2) = -66

f(5) = 3*5^2 + 2*5 =75+10=85
g(5) = 5-5 =0
(f-g)(5) = f(5) - g(5) = 85-0=85

(f o g)(x)
= f[g(x)]
= 3(x-5)^2 +2(x-5)
= 3(x^2 -10x+25) + 2x -10
= 3x^2 -30x + 75 + 2x - 10
= 3x^2 -28x + 65

R^2 at SCC