Answers>Maths>IB>Article

Solve for x in the following equation: e^x + 10e^(-x) = 7

First of all, we bring the 7 to the left side of the equation to get: ex-7+10e-x=0. Then, by multiplying both sides of the equation by ex, we can get an equation in the form of a quadratic equation: e2x-7ex+10=0. By setting y = ex, the quadratic nature of the equation can be seen as it simplifies to y2-7y+10=0. From GCSE maths, we know this can be factorised to obtain (y-5)(y-2)=0 and see that y=2 or y=5. The final step for this question is to sub ex back into the equation and solve for x using the ln laws: ex = 2 or 5; therefore x = ln2 or ln5.

LB
Answered by Leonardo B. Maths tutor

3840 Views

See similar Maths IB tutors

Related Maths IB answers

All answers ▸

The sum of the first and third term of a geometric sequence is 72. The sum to infinity of this sequence is 360, find the possible values of the common ratio, r.


Find the differential of y=arcsinx


Finding complex numbers using DeMoivre's Theorem


The sum of the first n terms of an arithmetic sequence is Sn=3n^2 - 2n. How can you find the formula for the nth term un in terms of n?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning