From what I can tell, this can't be simplified, because there are no factors of 42 that are perfect squares. I would leave it as the square root of 42.
Px + qy = r
2px - qy = 2r
----------------add
3px = 3r
x = 3r/3p
x = r/p
Remark
First of all you have to declare the meaning of g(f(x)) After you have done that, you have to make the correct substitution.
Givens
f(x) = 4x^2 + x + 1
g(x) = x^2 - 2
Discussion
What the given condition g(f(x)) means is that you begin with g(x). Write down g(x) = x^2 - 2
Wherever you see an x on either the left or right side of the equation, you put fix)
Then wherever you see f(x) on the right you put in what f(x) is equal to.
Solution
g(x) = x^2 - 2
g(f(x)) = (f(x))^2 - 2
g(f(x)) = [4x^2 + x + 1]^2 - 2
f(x)^2 =
4x^2 + x + 1
<u>4x^2 + x + 1</u>
16x^4 + 4x^3 + 4x^2
4x^3 + x^2 + x
<u> 4x^2 + x + 1</u>
16x^4 + 8x^3 + 9x^2 + 2x + 1
Answer
g(f(x)) = 16x^4 + 8x^3 + 9x^2 + 2x + 1 - 2
g(f(x)) = 16x^4 + 8x^3 + 9x^2 + 2x - 1
Your answer is correct :)
