By expressing cos(2x) in terms of cos(x) find the exact value of the integral of cos(2x)/cos^2(x) between the bounds pi/4 and pi/3.

cos(2x)=cos2(x)-sin2(x)=2cos2(x)-1
Therefore:cos(2x)/cos2(x)=(2cos2(x)-1)/cos2(x)=2cos2(x)/cos2(x) - 1/cos2(x)=2 - 1/cos2(x)=2 - sec2(x)
Integral of sec2(x) = tan(x)
Integral of 2 = 2x
[2x - tan(x)] between pi/4 and pi/3
= (2pi/3 - tan(pi/3)) -(pi/2 - tan(pi/4))
= (2pi/3 - sqrt(3)) - (pi/2 - 1)
= pi/6 - sqrt(3) + 1

HF
Answered by Hugo F. Maths tutor

7829 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Let y be a function of x such that y=x^3 + (3/2)x^2-6x and y = f(x) . Find the coordinates of the stationary points .


Solve 2^(3x-1) = 3


Find the values of the constants a and b for which ax + b is a particular integral of the differential equation 2y' + 5y = 10x. Hence find the general solution of 2y' + 5y = 10x .


Find the roots of this equation: y=(8-x)lnx


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