How do you verify cscx-sinx=cosxcotx?

1 Answer
Apr 16, 2016

Let's start by stating the identities that will be important to this problem:

Explanation:

The reciprocal identity (1): cscx = 1/sinx

The quotient identity (1): cotx = cosx/sinx

1/sinx - sinx = cosx(cosx/sinx)

Placing the left side on a common denominator:

1/sinx - sin^2x/sinx = cos^2x/sinx

(1 - sin^2x)/sinx = cos^2x/sinx

Applying the Pythagorean identity cos^2x + sin^2x = 1, we get:

cos^2x/sinx = cos^2x /sinx

Hopefully this helps!