Integral of sin^2(x) with respect to x

It is impossible to dirctly integrate sin^2(x) so we must transform it into something that can be integrated. Trigonometry can be used to do this. Recall the identity cos(2x) = cos^2(x) - sin^2(x) and cos^(x) + sin^2(x) = 1. These 2 indentities can be combined through a little bit of algebra to give; sin^2(x) = 0.5 -  0.5cos(2x). Now this is an expression which can be directly integrated! 

The integral of 0.5 - 0.5cos(2x)  is simply 0.5x -0.25sin(2x) 

OF

Related Maths A Level answers

All answers ▸

differentiate the following to find the equation for the gradient of the curve in terms of x and y: 3x^3 + 4x^2 + 5xy + 7y = 0


What is the y-coordinate minimum point of y = 3x^2 + x - 4


Factorise completely ( x − 4x^3)


Given that y = (( 4x + 1 )^3)sin(2x), find dy/dx.