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F(x) = 2x + 5 and g(x) = 5x², find (fog)(x)

User Aldur
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1 Answer

5 votes

Answer:
10x^2+5

Work Shown:


f(x) = 2x+5\\\\f(g(x)) = 2(g(x))+5\\\\f(g(x)) = 2(5x^2)+5\\\\f(g(x)) = 10x^2+5\\\\(f \circ g)(x) = 10x^2+5\\\\

Notice how I started with the outer function f(x). Then I replaced every x with g(x), followed by plugging in g(x) = 5x^2.

User Substantial
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