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

Last updated at Aug. 11, 2021 by Teachoo

Last updated at Aug. 11, 2021 by Teachoo

Transcript

Ex 8.4, 5 Prove the following identities, where the angles involved are acute angles for which the expressions are defined. (vi) ((1 + sin )/(1 sin )) = sec A + tan A Taking L.H.S ((1 + sin )/(1 sin )) Rationalizing denominator Multiplying (1 + sin A) in numerator and denominator = (((1 + sin )(1 + sin ) )/((1 sin )(1 + sin ) )) = (((1 + sin )2 )/(12 2 )) = (((1 + sin )2 )/(1 2 )) = (((1 +sin )2 )/( 2 )) = (((1 + )/( ))^2 ) = (1 + sin )/cos = 1/cos + sin /cos = sec A + tan A = R.H.S Hence proved

Ex 8.4

Ex 8.4, 1

Ex 8.4, 2 Important

Ex 8.4, 3 (i) Important

Ex 8.4, 3 (ii)

Ex 8.4, 4 (i) [MCQ]

Ex 8.4, 4 (ii) [MCQ] Important

Ex 8.4, 4 (iii) [MCQ] Important

Ex 8.4, 4 (iv) [MCQ]

Ex 8.4, 5 (i) Important

Ex 8.4, 5 (ii)

Ex 8.4, 5 (iii) Important

Ex 8.4, 5 (iv) Important

Ex 8.4, 5 (v) Important

Ex 8.4, 5 (vi) You are here

Ex 8.4, 5 (vii) Important

Ex 8.4, 5 (viii)

Ex 8.4, 5 (ix) Important

Ex 8.4, 5 (x)

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