Question

how do I simplify 2cos2ysin2y

Answer 1

Hoot! You just asked your first question! Hang tight while I find people to answer it for you. You can thank people who give you good answers by clicking the 'Good Answer' button on the right!

Answer 2

You apply the double angle formula for Sine which states:
\[\sin(2x)=2\sin(x)\cos(x)\]
From here You can work backwards and say: Let x=2y.
Or:
\[2\sin(2y)\cos(2y)=2\sin(x)\cos(x)=\sin(2x)\]
But since you let x=2y it becomes:
\[\sin(4y)\]

Answer 3

That helps - thank you very much!

Answer 4

No problem :)