Advertisements
Advertisements
प्रश्न
If sin 3A = 1 and 0 < A < 90°, find cos 2A
Advertisements
उत्तर
sin 3A = 1
sin 3A = sin90°
3A = 90°
A = 30°
cos 2A = cos 2(30°)
= cos 60°
= `(1)/(2)`
APPEARS IN
संबंधित प्रश्न
Calculate the value of A, if (sin A - 1) (2 cos A - 1) = 0
From the given figure,
find:
(i) cos x°
(ii) x°
(iii) `(1)/(tan^2 xx°) – (1)/(sin^2xx°)`
(iv) Use tan xo, to find the value of y.
Solve for x : cos2 30° + cos2 x = 1
Find the value of 'A', if cosec 3A = `(2)/sqrt(3)`
Solve for 'θ': cot2(θ - 5)° = 3
Find the value of 'x' in each of the following:
The perimeter of a rhombus is 100 cm and obtuse angle of it is 120°. Find the lengths of its diagonals.
Express each of the following in terms of trigonometric ratios of angles between 0° and 45°: cos72° - cos88°
Evaluate the following: `(5cot5° cot15° cot25° cot35° cot45°)/(7tan45° tan55° tan65° tan75° tan85°) + (2"cosec"12° "cosec"24° cos78° cos66°)/(7sin14° sin23° sec76° sec67°)`
If A + B = 90°, prove that `(tan"A" tan"B" + tan"A" cot"B")/(sin"A" sec"B") - (sin^2"B")/(cos^2"A")` = tan2A
