Advertisements
Advertisements
प्रश्न
The value of cos2 17° − sin2 73° is
पर्याय
1
\[\frac{1}{3}\]
0
-1
उत्तर
We have:
`cos^2 17°-sin^2 73°`
= `cos^2(90°-73°)-sin^2 73°`
=` sin^2 73°-sin^2 73°`
= 0
APPEARS IN
संबंधित प्रश्न
If the angle θ = -60° , find the value of sinθ .
Without using trigonometric tables, evaluate the following:
`( i)\frac{\cos37^\text{o}}{\sin53^\text{o}}\text{ }(ii)\frac{\sin41^\text{o}}{\cos 49^\text{o}}(iii)\frac{\sin30^\text{o}17'}{\cos59^\text{o}\43'}`
Prove the following trigonometric identities.
(cosecθ + sinθ) (cosecθ − sinθ) = cot2 θ + cos2θ
Solve.
sin42° sin48° - cos42° cos48°
Evaluate:
`sin80^circ/(cos10^circ) + sin59^circ sec31^circ`
Use tables to find the acute angle θ, if the value of cos θ is 0.9848
Use tables to find the acute angle θ, if the value of cos θ is 0.6885
If A and B are complementary angles, prove that:
cot A cot B – sin A cos B – cos A sin B = 0
If A and B are complementary angles, prove that:
cosec2 A + cosec2 B = cosec2 A cosec2 B
Write the acute angle θ satisfying \[\cos B = \frac{3}{5}\]
Write the value of cos 1° cos 2° cos 3° ....... cos 179° cos 180°.
If 16 cot x = 12, then \[\frac{\sin x - \cos x}{\sin x + \cos x}\]
The value of tan 10° tan 15° tan 75° tan 80° is
If 5θ and 4θ are acute angles satisfying sin 5θ = cos 4θ, then 2 sin 3θ −\[\sqrt{3} \tan 3\theta\] is equal to
tan 5° ✕ tan 30° ✕ 4 tan 85° is equal to
Prove that:
\[\frac{sin\theta \cos(90° - \theta)cos\theta}{\sin(90° - \theta)} + \frac{cos\theta \sin(90° - \theta)sin\theta}{\cos(90° - \theta)}\]
A, B and C are interior angles of a triangle ABC. Show that
If ∠A = 90°, then find the value of tan`(("B+C")/2)`
In the case, given below, find the value of angle A, where 0° ≤ A ≤ 90°.
sin (90° - 3A).cosec 42° = 1.
Find the value of the following:
`((cos 47^circ)/(sin 43^circ))^2 + ((sin 72^circ)/(cos 18^circ))^2 - 2cos^2 45^circ`
Find the value of the following:
sin 21° 21′
