Verify that this is an identity.

1. (tan u - cot u) / (tan u + cot u) is an identity.

(tan u - cot u) / (tan u + cot u)

= [(sin u/cos u) - (cos u/sin u)] / [(sin u/cos u) + (cos u/sin u)]

= (sinē u - cosē u) / (sinē u + cosē u)

= sinē u - cosē u

is there any other mid steps that would be good to include?

Re: Verify that this is an identity.

Quote:

Originally Posted by

**JamesBond16** 1. (tan u - cot u) / (tan u + cot u) is an identity.

(tan u - cot u) / (tan u + cot u)

= [(sin u/cos u) - (cos u/sin u)] / [(sin u/cos u) + (cos u/sin u)]

This is a BIG jump. You might want to break down the steps.

Quote:

= (sinē u - cosē u) / (sinē u + cosē u)

= sinē u - cosē u

is there any other mid steps that would be good to include?

Re: Verify that this is an identity.

Hello, JamesBond16!

(tan u - cot u) / (tan u + cot u) is *not* an identity.

Re: Verify that this is an identity.

Quote:

Originally Posted by

**Soroban** Hello, JamesBond16!

(tan u - cot u) / (tan u + cot u) is *not* an identity.

Of course you're right, but it looks like JamesBond16 was proving the identity:

(tan u - cot u) / (tan u + cot u) = sinē u - cosē u .