Prove that:---=cot(x)

sin(2x)

1-cos(2x)

I've worked it down to simply cosx on the left side, but the other side is very annoying and confusing.

Printable View

- May 14th 2010, 04:42 PMtallguywhoplaysguitarDouble angle Prove question
**Prove that:**---=cot(x)

sin(2x)

1-cos(2x)

I've worked it down to simply cosx on the left side, but the other side is very annoying and confusing. - May 14th 2010, 08:06 PMSoroban
Hello, tallguywhoplaysguitar!

We need some double-angle identities:

. .

. .

Quote:

Prove that: .

We have: .

- May 15th 2010, 10:48 AMtallguywhoplaysguitar
thank you