LIVE Course for free

Rated by 1 million+ students
Get app now
0 votes
50 views
in Trigonometry by (71.6k points)
closed by
Prove the following identity, where the angles involved are acute angles for which the expressions are defined.
(vii) `(sintheta-2sin^3theta)/(2cos^3theta-costheta)=tantheta`

1 Answer

0 votes
by (71.5k points)
selected by
 
Best answer
`L.H.S. =(sintheta - 2sin^3theta)/(2cos^3theta-costheta)`
`=(sintheta(1-2sin^2theta))/(costheta(2cos^2theta-1))`
`=tantheta(cos^2theta+sin^2theta-2sin^2theta)/(2cos^2theta-cos^2theta-sin^2theta)`
`=tantheta(cos^2theta-sin^2theta)/(cos^2theta-sin^2theta)`
`=tantheta=R.H.S.`

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...