Thread: Integrating trig functions

This question is more about my understanding than solving. I've done the question asking me to show that the differential of cotx is -cosec^2x by putting it in the form cosx/sinx. Then the second part says "Hence find the exact value of the integral of cot^2x between pi/2 and pi/4". I don't really see how the first part helps with that.

Many thanks in advance.

Originally Posted by JeWiSh

This question is more about my understanding than solving. I've done the question asking me to show that the differential of cotx is -cosec^2x by putting it in the form cosx/sinx. Then the second part says "Hence find the exact value of the integral of cot^2x between pi/2 and pi/4". I don't really see how the first part helps with that.

Many thanks in advance.

From the basic Pythagorean identity: .

And from the previous answer you know what the integral of is ....