solve 3sinh^2(2x) + 11sinh(2x) = 4 for x, giving your answer(s) in terms of the natural log.

3sinh^2(2x) + 11sinh(2x) - 4 = 0 --> (3sinh(2x) - 1)(sinh(2x) + 4) = 0 --> sinh(2x) = 1/3, sinh(2x) = -4(e^(2x) - e^(-2x))/2 = 1/3 --> e^(4x) -(2/3)e^(2x) - 1 = 0 --> e^(2x) = 1/3 + 2sqrt(5)/3 the other solution is negative, e^2x > 0--> x = (1/2)ln(1/3 + 2sqrt(5)/3)(e^(2x) - e^(-2x))/2 = -4 --> e^(4x) - 8e^(2x) - 1 = 0 --> e^(2x) = 4 + sqrt(34) sqrt(34) > 4 so other solution is negative--> x = (1/2)ln(4 + sqrt(34))

WM
Answered by William Michael O. Further Mathematics tutor

2554 Views

See similar Further Mathematics A Level tutors

Related Further Mathematics A Level answers

All answers ▸

How do I find the vector/cross product of two three-dimensional vectors?


(FP1) Given k = q + 3i and z = w^2 - 8w* - 18q^2 i, and if w is purely imaginary, show that there is only one possible non-zero value of z


What is De Moivre's theorem?


I do not understand this topic and particularly this example. In the class the result was found out but I still do not get it. How did the teacher came up with this outcome?


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:

© 2026 by IXL Learning