Integrate sin^2x
![Integrate sin^2x](integrate-sin_2_x/step-1-integrate-sin_2_x.gif)
To integrate sin^2x, also written as ∫sin2x dx, sin squared x, and (sin x)^2, we start by using standard trig identities to simplify the integral.
![Trig Identity 1](integrate-sin_2_x/step-2-trig-identity.gif)
We start by using the standard trig identity sin2x+cos2x=1 and rearrange it for sin2x. This is basic and straightforward.
![Trig Identity 2](integrate-sin_2_x/step-3-trig-identity.gif)
We then recall another standard trig identity for double angle where cos2x=cos2x-sin2x, and rearrange it for cos2x.
![Substitute Trig Identities](integrate-sin_2_x/step-4-substitution-of-trig-identity.gif)
We substitute the second trig identity into the first and rearrange for sin2x.
![Equivalent Integration](integrate-sin_2_x/step-5-equivalent-integration.gif)
As you can see, we now have an equivalent integral that is the same as the original, but easier to perform. Although the ½ fraction is easy to integrate, we need to focus on integrating the cos2x term, which we achieve using the u substitution method.
![u Substitution Method](integrate-sin_2_x/step-6-integrate-cos2x-using-u-substitution-method.gif)
Using the u substitution, we integrate cos2x dx to give part of the answer.
![Substitution and Final Answer](integrate-sin_2_x/step-7-substitution-and-final-answer.gif)
We substitute the result we gained from integrating cos2x, and then simplify to give the final answer.