- #1
geegeet
- 3
- 0
Homework Statement
I keep getting what I think is the "right answer", but it's not one of my choices :^(
Here are the problems and answer choices.
1).
2).
Homework Equations
nothing really...or at least I don't think besides the fact that e^-x = 1/e^x
The Attempt at a Solution
1).
x + 14 = 2 g^( - 1) ( x )
(x + 14) / 2 = g^( - 1) ( x)
x - 3 = 4 f^( - 1) ( x)
( x - 3) / 4 = f^( - 1) ( x)
g^( - 1) o f^( - 1) ( x) = (x + 53) / 8
I get this for number 1, but it is not one of the answer choices!
2).
6 = 7e^x + e^(-x )
Let e^x = t, (t > 0), thus e^(-x) = 1/t
6 = 7t + 1/t
Multiplying each side by t
6t = 7t² + 1
7t² - 6t + 1 = 0
t = (3 ± √2)/7
e^x = t ==> x = ln (t)
x = ln [(3 + √2)/7] or x = ln [(3 − √2)/7]
I get this for number 2, but it is also not one of the answer choices!
