Check sibling questions

Ex 8.4, 5 (ii) - Chapter 8 Class 10 Introduction to Trignometry (Term 1)

Last updated at March 29, 2023 by

Ex 8.4, 5 - Chapter 8 Class 10 Introduction to Trignometry - Part 3

Ex 8.4, 5 - Chapter 8 Class 10 Introduction to Trignometry - Part 4

Get live Maths 1-on-1 Classs - Class 6 to 12

Book 30 minute class for ₹ 499 ₹ 299

Transcript

Ex 8.4, 5 Prove the following identities, where the angles involved are acute angles for which the expressions are defined. (ii) "cos A" /"1 + sin A" +"1 + sin A" /"cos A" =2 sec A Taking L.H.S (cos )/(1 + sin )+(1 + sin )/(cos ) = (cos (cos ) + (1 + sin )(1 + sin ) )/((1 + sin )(cos )) = ( 2 + (1 + sin )2)/((1 + sin )(cos )) = ( 2 + 1^2 + 2 + 2 sin )/((1 + sin )(cos )) = (( 2 + 2 ) + 1 + 2 sin )/((1 + sin )(cos ) ) = (1 + 1 + 2 sin )/((1 + sin )(cos ) ) = (2 + 2 sin )/((1 + sin )(cos ) ) = (2(1+ sin ))/((1 + sin )(cos ) ) = 2/(cos ) = 2 1/cos = 2 sec A = R.H.S L.H.S = R.H.S Hence proved

Ask a doubt
Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.