A Level Maths Integration

Not really sure what to do with the 6cos^2(4x) on this. I tried what I thought was reversing the chain rule, but I didn't seem to make much progress :confused:

Any help would be appreciated :smile:

Reply 1

mqb2766

Original post by cloudii

Not really sure what to do with the 6cos^2(4x) on this. I tried what I thought was reversing the chain rule, but I didn't seem to make much progress :confused:

Any help would be appreciated :smile:

The limits seem to be hinting towards a trig(8x)?

Reply 2

Mocha Latte

Original post by cloudii

Not really sure what to do with the 6cos^2(4x) on this. I tried what I thought was reversing the chain rule, but I didn't seem to make much progress :confused:

Any help would be appreciated :smile:

Hint: use the double angle identity

Reply 3

cloudii

Original post by mqb2766

The limits seem to be hinting towards a trig(8x)?

I'm obviously missing something, do you think you could explain why it would be a trig(8x)? Is it something to do with a trig identity?

Reply 4

mqb2766

Original post by cloudii

I'm obviously missing something, do you think you could explain why it would be a trig(8x)? Is it something to do with a trig identity?

Double angle converts a squared term to a single trig term.

There are a few ways you could go, even IBP, but a double angle is probably the simplest.