Solve for 0<x≤2π, cos^2(x)-3cos(x)=5sin^2(x)-2, giving all answers exactly

Use the identity cos^2(x)+sin^2(x)=1, to change the 5sin^(x) into 5-5cos^2(x) and rearrange. Let y=sin(x) and solve the rearranged quadratic (6y^2-3y-3) for y and find the value of x for each solution. y= -0.5, 1 leads to x=2π/3, 4π/3, 2π, explained with cast diagram if needs be.

Answered by Ben M. Maths tutor

4344 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Solve 4cos(2x )+ 2sin(2x) = 1 given -90° < x < 90°. Write 4cos(2x )+ 2sin(2x) in the form Rcos(2x - a), where R and a are constants.


Solve the equation 8x^6 + 7x^3 -1 = 0


Use integration by parts to integrate ∫ xlnx dx


Express cos2x in the form a*cos^2(x) + b and hence show that the integral of cos^2(x) between 0 and pi/2 is equal to pi/a.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences