SOLUTION: 15. If f(x) =2x2+1 and g(x)=x-3, find (f o g)(x). a. (f o g)(x) = 2x 2 - 17 b. (f o g)(x) = 2x 2 - 12x + 19 c. (f o g)(x) = 2x 2 - 2 d. (f o g)(x) = 2x 2 - 12x + 13 * I di

Algebra ->  Trigonometry-basics -> SOLUTION: 15. If f(x) =2x2+1 and g(x)=x-3, find (f o g)(x). a. (f o g)(x) = 2x 2 - 17 b. (f o g)(x) = 2x 2 - 12x + 19 c. (f o g)(x) = 2x 2 - 2 d. (f o g)(x) = 2x 2 - 12x + 13 * I di      Log On


   



Question 329096: 15. If f(x) =2x2+1 and g(x)=x-3, find (f o g)(x).
a. (f o g)(x) = 2x 2 - 17
b. (f o g)(x) = 2x 2 - 12x + 19
c. (f o g)(x) = 2x 2 - 2
d. (f o g)(x) = 2x 2 - 12x + 13
* I did fog(x)=f{g(x)}=fx-3)=2x2+1=2{x-3}^2+1=4x^2-24x+37.
But thats not a answer choice. Stuck!!!

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
You're correct up to expanding the function,
2%7Bx-3%7D%5E2%2B1=4x%5E2-24x%2B37
The leading coefficient should be a 2 and not a 4.
You seem to have doubled up somehow.
.
.
.
f%28x%29=2x%5E2%2B1+
g%28x%29=x-3
f%28g%29=2g%5E2%2B1
f%28g%29=2%28x-3%29%5E2%2B1
f%28g%29=2%28x%5E2-6x%2B9%29%2B1
f%28g%29=2x%5E2-12x%2B18%2B1
f%28g%29=2x%5E2-12x%2B19