Asked by tina
Solve the logarithmic equation. Express your solutions in exact form only.
18e^-x -e^x=7
18e^-x -e^x=7
Answers
Answered by
Reiny
18/e^x - e^x = 7
let e^x = a
18/a - a - 7 = 0
18 - a^2 - 7a = 0
a^2 + 7a - 18 = 0
(a+9)(a-2) = 0
a = -9 or a = 2
then
e^x = -9 ----> no solution
or
e^x = 2
x = ln 2
let e^x = a
18/a - a - 7 = 0
18 - a^2 - 7a = 0
a^2 + 7a - 18 = 0
(a+9)(a-2) = 0
a = -9 or a = 2
then
e^x = -9 ----> no solution
or
e^x = 2
x = ln 2
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.