Trigonometry & Inverse Trigonometry
Trigonometric Ratios & Identities
nta_pyq_2025_jan
Grade 11
Question:
The value of (sin 70 ) (cot 10 cot 70 - 1) is ∘ ∘ ∘
Step-by-Step Solution
Key Concept: Apply the core result for trigonometric identities and simplify using the given constraints.
(sin 70 ) (cot 10 cot 70 - 1) ∘ ∘ ∘ ∘ (2) = sin 70 ∘ cot 10 ∘ cot 70 - sin 70 ∘ = cot 10 cos 70 - sin 70 ∘ ∘ ∘ ∘ cos 10 cos 70 - sin 70 sin 10 = ∘ sin 10 ∘ ∘ cos(10 + 70 ) = ∘ sin 10 ∘ cos 80 = = 1 ∘ sin 10
Correct Answer: 2