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

2603 Views

See similar Further Mathematics A Level tutors

Related Further Mathematics A Level answers

All answers ▸

Prove that sum(k) from 0 to n is n(n+1)/2, by induction


Are we able to represent linear matrix transformations with complex numbers?


Use De Moivre's Theorem to show that if z = cos(q)+isin(q), then (z^n)+(z^-n) = 2cos(nq) and (z^n)-(z^-n)=2isin(nq).


Differentiate arctan of x with respect to x.


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