alleryStart learning →Evaluate cos²15° − sin²15°.
A1
B√2/2
C1/2
D√3/2
Answer & Solution
Correct answer: D. √3/2
The expression is cos 30° by the double-angle formula, which is √3/2.
Keep practising Trigonometry
Browse all Trigonometry questions for SSC CGL, or explore more Quantitative Aptitude topics.
Related questions
From the top of a 90 m tower the angle of depression of a boat is 60°. How far is the boatA pole is broken so its top touches the ground 6 m from the base at 30° to the ground. FinIf tan(A + B) = √3 and tan(A − B) = 1/√3, find A.If sin(A + B) = 1 and cos(A − B) = √3/2 for acute angles, find A and B.Evaluate sin 90° + cos 0° + tan 45°.In a right triangle, cot θ is the ratio ofUsing cos²θ = (1 + cos 2θ)/2, find cos²15°.What is the minimum value of sec²θ + cosec²θ?