SOLUTION: Find (fog)(x) and (gof)(x) for the pair of functions {{{(F)(x)=2x^2-5x}}} {{{(g)(x)= 2(Sqrt(x+12))}}}

Algebra ->  Functions -> SOLUTION: Find (fog)(x) and (gof)(x) for the pair of functions {{{(F)(x)=2x^2-5x}}} {{{(g)(x)= 2(Sqrt(x+12))}}}      Log On


   

Question 514271: Find (fog)(x) and (gof)(x) for the pair of functions
%28F%29%28x%29=2x%5E2-5x %28g%29%28x%29=+2%28Sqrt%28x%2B12%29%29
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find (fog)(x) and (gof)(x) for the pair of functions
(F)(x)=2x^2-5x ; (g)(x)= 2(Sqrt(x+12))
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fog(x) = f[g(x)] = f[2sqrt(x+12)]
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= 2[2sqrt(x+12)]^2-5[2sqrt(x+12)]
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= 2[4(x+12)] - 10sqrt(x+12)
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= 8x+24 - 10sqrt(x+12)
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gof(x) = g[f(x)] = g[2x^2-5x]
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= 2sqrt[2x^2-5x+12]
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Cheers,
Stan H.