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

8076 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

A curve has an equation of y = 20x - x^2 - 2x^3, with one stationary point at P=-2. Find the other stationary point, find the d^2y/dx^2 to determine if point P is a maximum or minium.


differentiate y=(5x-2)^5


Use integration by parts to evaluate: ∫xsin(x) dx.


Find the stationary points on y = x^3 + 3x^2 + 4 and identify whether these are maximum or minimum points.


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