Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • NCERT
  • Prove the following identities, where the angles involved are acute angles for which the expressions are defined. (cosec A - sin A) (sec A - cos A) = 1/tan A + cot A

5. Prove the following identities, where the angles involved are acute angles for which the expressions are defined.

   (ix)\:(cosec A-\sin A)(\sec A-\cos A)=\frac{1}{\tan A+\cot A}

                      [Hint : Simplify LHS and RHS separately]

Answers (1)

best_answer

We need to prove-
(coesc A-\sin A)(\sec A-\cos A)=\frac{1}{\tan A+\cot A}
Taking LHS;
\\\Rightarrow (cosec A-\frac{1}{\csc A})(\sec A-\frac{1}{\sec A})\\\\ \Rightarrow\frac{(cosec^2-1)}{cosec A}\times\frac{\sec^2A-1}{\sec A}\\\\ \Rightarrow\frac{\cot^2A}{cosec A}.\frac{\tan^2A}{\sec A}\\\\ \Rightarrow\sin A .\cos A

Taking RHS;

\\\Rightarrow\frac{1}{\sin A/\cos A+\cos A/\sin A}\\\\ \Rightarrow\frac{\sin A .\cos A}{\sin^2A+\cos^2A}\\\\ \Rightarrow \sin A.\cos A

LHS = RHS

Hence proved.

Posted by

manish

View full answer

Similar Questions

Trending Articles/News

anam-khan

CBSE 2026 10th Exam May 15 LIVE: Session 2 maths 'easier'; question paper with answer key, analysis
anam-khan

CBSE 10th Admit Card 2026 (OUT) LIVE: Phase 2 hall ticket issued at cbse.gov.in; datesheet, paper timings
anam-khan

CBSE 2nd Board exam 2026 class 10 admit card out at cbse.gov.in; steps to download

Latest Question