SOLUTION: Can I get some help please? Functions and Relations If f(x)=3x^2-4x+5 and g(x)=4x-3 How do I find (fog)(x) When finding (fog)(x) where ever you see x in the equation o

Algebra ->  Functions -> SOLUTION: Can I get some help please? Functions and Relations If f(x)=3x^2-4x+5 and g(x)=4x-3 How do I find (fog)(x) When finding (fog)(x) where ever you see x in the equation o      Log On


   



Question 879765: Can I get some help please?
Functions and Relations
If f(x)=3x^2-4x+5 and g(x)=4x-3
How do I find
(fog)(x)
When finding (fog)(x) where ever you see x in the equation of f(x) you will replace the g(x) equation
(fog)(x)= 3(4x-3)^2 -4(4x-3)+5
= 3(16x^2-12x-12x+9)-16x+12+5
= 3(16x^2-24x+9)-16x+17
= 48x^2-72x+27-16x+17
= 48x^2+(-72x-16x)+(27+17)
= 48x^2-88x+44
(fog)(x)= 4(12x^2-22x+11)
and
(gof)(x)
To find (gof)(x)where ever you see x in the g(x) equation you would replace it with the f(x) equation
g(x) = 4(3x^2-4x+5)-3
= 12x^2-16x+20-3
g(x) = 12x^2-16x+17
Thank you!!

Answer by BigToosie(32) About Me  (Show Source):