How do you verify the identify costhetacottheta+sintheta=csctheta?

2 Answers
Mar 26, 2018

"see explanation"

Explanation:

"using the "color(blue)"trigonometric identities"

•color(white)(x)cottheta=costheta/sintheta" and "csctheta=1/sintheta

•color(white)(x)sin^2theta+cos^2theta=1

"consider the left side"

costhetaxxcostheta/sintheta+sintheta

=cos^2theta/sintheta+sin^2theta/sintheta

=(cos^2theta+sin^2theta)/sintheta

=1/sintheta=csctheta=" right side "rArr"verified"

Mar 26, 2018

see below

Explanation:

L.H.S: costhetaxxcot theta +sin theta
=cos theta xx(frac{cos theta}sin theta) +sin theta
=cos^2theta//sin theta +sin theta
=frac{cos^2 theta +sin^2 theta}sin theta
=1//sin theta
="cosec "theta which is the R.H.S