Posted by Saud on Wednesday, November 21, 2012 at 11:44am.
using the usual notation,
f(x) = x^2+3
g(x) = 2x+1
fg = f(x)*g(x) = (x^2+3)(2x+1) = 2x^3 + x^2 + 6x + 3
f(x) = 12g^-1(x)
g^-1(x) = (x-1)/2
so, solve x^2+3 = 12(x-1)/2
x^2+3 = 6x-6
x^2 - 6x + 9 = 0
(x-3)^2 = 0
x = 3
If by fg you meant f◦g (that is, f(g(x))), then
since f(x) = x^2+3,
f(g) = g^2+3 = (2x+1)^2+3 = 4x^2 + 4x + 4
Related Questions
Math, Still Need Help! - Label each statement TRUE or FALSE. a. The sum of two ...
Math AP Calc - Label each statement TRUE or FALSE. a. The sum of two one-to-one ...
Math - Label each statement TRUE or FALSE. a. The sum of two one-to-one ...
Alegbra - I need to have some problems checked and I need help with one of them...
Maths - Thanks guys for your response!!!! x I have another one. If the two ...
math - How do I know that x^2-7=y is a function? thanks you know its a function ...
Biology - Need help with this one: c)The cytoskeleton of eukaryotes serves many ...
Maths - The values for x when f(x) = 0 are: x=-2 and x=3 My question is: The ...
Maths (URGENT) - The values for x when f(x) = 0 are: x=-2 and x=3 My question is...
Algebra-Functions - Could you please check my answers and help me with two ...
For Further Reading
