
Learn in your speed, with individual attention - Teachoo Maths 1-on-1 Class
Ex 8.3
Ex 8.3, 2 Important
Ex 8.3, 3 (i) [MCQ]
Ex 8.3, 3 (ii) [MCQ] Important
Ex 8.3, 3 (iii) [MCQ] Important
Ex 8.3, 3 (iv) [MCQ]
Ex 8.3, 4 (i) Important
Ex 8.3, 4 (ii)
Ex 8.3, 4 (iii) Important
Ex 8.3, 4 (iv) Important You are here
Ex 8.3, 4 (v) Important
Ex 8.3, 4 (vi)
Ex 8.3, 4 (vii) Important
Ex 8.3, 4 (viii)
Ex 8.3, 4 (ix) Important
Ex 8.3, 4 (x)
Question 1 (i) Important Deleted for CBSE Board 2024 Exams
Question 1 (ii) Deleted for CBSE Board 2024 Exams
Last updated at Aug. 16, 2023 by Teachoo
Ex 8.3, 4 Prove the following identities, where the angles involved are acute angles for which the expressions are defined. ("1 + sec" A)/"sec A" ="sin2 A" /"1 – cos A" "[Hint : Simplify LHS and RHS separately]" (1 + sec𝐴)/sec〖 𝐴〗 = 1/sec〖 𝐴〗 +sec〖 𝐴〗/sec〖 𝐴〗 = 1/sec〖 𝐴〗 +1 = cos A + 1 (𝒔𝒊𝒏𝟐 𝑨)/(1 − cos𝐴 ) = (𝟏 − 𝒄𝒐𝒔𝟐 𝑨)/(1 − cos𝐴 ) = (12 − 𝑐𝑜𝑠2 𝐴)/(1 − cos𝐴 ) = ((1 − 𝑐𝑜𝑠 𝐴)(1+ cos〖𝐴)〗)/(1 − cos𝐴 ) = 1 + cos A ∴ L.H.S = R.H.S Hence proved