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2013-12-13T19:47:45-02:00
F(x) = x²+2x
g(x) = 1-3x

a) f(g(x)) = f(1-3x) = (1-3x)²+2x = 1-6x+9x²+2x = 9x²-4x+1
b) g(f(x)) = g(x²+2x) = 1 - 3.(x²+2x) = 1 - 3x² - 6x 
c) f(f(x)) = f(x²+2x) = [(x²+2x)]² + 2.(x²+2x) = x^4+4x²+4x² + 2x²+4x = 
x^4+10x²+4x
d) g(g(x)) = g(1-3x) = 1 - 3.(1-3x) = 1 -3+9x = 9x-2
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