SOLUTION: Use f(x) = 4x^2 and g(x) = x-8/2 to evaluate the expression. a.) fog(4) b.) gof (-3)

Algebra ->  Functions -> SOLUTION: Use f(x) = 4x^2 and g(x) = x-8/2 to evaluate the expression. a.) fog(4) b.) gof (-3)      Log On


   

Question 725791: Use f(x) = 4x^2 and g(x) = x-8/2 to evaluate the expression.
a.) fog(4)
b.) gof (-3)
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Use f(x) = 4x^2 and g(x) = x-8/2 to evaluate the expression.
a.) fog(4)
=f[g(x)]
=f[(x-8)/2]
=f[4*((x-8)/2)^2]
=f[4*(x^2-16x+64)/4]
=16-64+64
=16
b.) gof (-3)
=g[f(x)]
=g[4x^2]
=(4x^2-8)/2)
=4(x^2-2)/2
=2(x^2-2)
=2(9-2)
=14