Ex 8.3

Ex 8.3, 1

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 You are here

Ex 8.3, 4 (ii)

Ex 8.3, 4 (iii) Important

Ex 8.3, 4 (iv) Important

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 2025 Exams

Question 1 (ii) Deleted for CBSE Board 2025 Exams

Last updated at April 16, 2024 by Teachoo

Ex 8.3, 4 Prove the following identities, where the angles involved are acute angles for which the expressions are defined. (i) (cosec θ – cot θ)2 = (1 − 𝑐𝑜𝑠" " θ)/(1 + cosθ ) Solving L.H.S (cosec θ – cot θ)2 We need to make it in terms of cos θ & sin θ = (1/sin𝜃 − cos𝜃/sin𝜃 )^2 = ((1 − cos𝜃)/sin𝜃 )^2 = ((1 − cos〖𝜃)2〗)/(𝒔𝒊𝒏𝟐 𝜽) = ((1 − 〖cos 𝜃〗〖)2〗)/(1 − 𝑐𝑜𝑠2𝜃) = ((1 − 〖cos 𝜃〗〖)2〗)/(1 − 𝑐𝑜𝑠2𝜃) = ((1 −〖 cos 𝜃〗〖)2〗)/(𝟏𝟐 − 𝒄𝒐𝒔𝟐𝜽) = (1− cos 𝜃)^2/((𝟏 + 𝐜𝐨𝐬𝜽)(𝟏 − 𝐜𝐨𝐬𝜽)) = (𝟏 −〖 𝐜𝐨𝐬〗𝜽)/(𝟏 +〖 𝐜𝐨𝐬〗𝜽 ) = RHS Hence proved