How do you verify the identity (2+cscthetasectheta)/(cscthetasectheta)=(sintheta+costheta)^2?

1 Answer
Sep 1, 2016

You will need the following identities to prove this identity.

cscbeta = 1/sinbeta

secbeta = 1/cosbeta

sin^2beta + cos^2beta = 1

Simplify the left-hand side and expand the right-hand side.

(2 + 1/sintheta xx 1/costheta)/(1/sintheta xx 1/costheta) = sin^2theta+ 2sinthetacostheta + cos^2theta

(2 + 1/(sinthetacostheta))/(1/(sinthetacostheta)) = 1 + 2sinthetacostheta

((2sinthetacostheta + 1)/(sinthetacostheta))/(1/(sinthetacostheta)) = 1 + 2sinthetacostheta

(2sinthetacostheta+ 1)/(sin thetacostheta) xx (sinthetacostheta)/1 = 1+ 2sinthetacostheta

2sinthetacostheta + 1 = 1 + 2sinthetacostheta

Identity proved!!

Hopefully this helps!