Advertisements
Advertisements
प्रश्न
Find the values of:
cos 75°
Advertisements
उत्तर
cos 75° = cos(45° + 30°)
= cos 45° cos 30° – sin 45° sin 30°
= `1/sqrt(2)* sqrt(3)/2 - 1/sqrt(2)*1/2`
= `sqrt(3)/(2sqrt(2)) - 1/(2sqrt(2)`
= `(sqrt(3) - 1)/(2sqrt(2)`
APPEARS IN
संबंधित प्रश्न
Find the value of:
sin 15°
Find the values of:
tan 105°
Find the values of:
cot 225°
Find the value of sin 690°.
Find the value of :
sin (495°)
Find the value of :
cos 315°
Find the value of:
sec (–855°)
Find the value of :
cosec 780°
Prove the following:
sec 840° . cot (– 945°) + sin 600° tan (– 690°) = `3/2`
Select the correct option from the given alternatives :
Let 0 < A, B < `pi/2` satisfying the equation 3 sin2A + 2 sin2B = 1 and 3 sin 2A − 2 sin 2B = 0 then A + 2B is equal to ______
Prove the following:
cosec 48° + cosec 96° + cosec 192° + cosec 384° = 0
Prove the following:
sin 36° = `(sqrt(10 - 2sqrt(5)))/4`
Prove the following:
sin47° + sin61° − sin11° − sin25° = cos7°
If a = sin 175°+ cos 175°, then ______.
`(1 - 2[cos 60^circ - cos 80^circ])/(2 sin 10^circ)` = ______.
The value of sin 495° is ______.
The value of `cos((41π)/4)` is ______.
The value of `cos π/8 + cos (3π)/8 + cos (5π)/8 + cos (7π)/8` is ______.
If `cosA/3 = cosB/4 = 1/5, - π/2 < A < 0` and `- π/2 < B < 0`, then the value of 2 sin A + 4 sin B is ______.
The value of `(cot 54^circ)/(tan 36^circ) + (tan 20^circ)/(cot 70^circ)` is ______.
If cos θ = `- sqrt(3)/2` and sin α = `-3/5`, where θ does not and α lies in the third quadrant, then `(2 tan α + sqrt(3) tan θ)/(cot^2 θ + cos alpha)` is equal to ______.
If tan θ = `1/sqrt(7)`, then `(("cosec"^2θ - sec^2θ))/(("cosec"^2θ + sec^2θ))` is equal to ______.
In a ΔABC, if ∠A = `π/2`, then cos2 B + cos2 C is equal to ______.
If sin A + sin B + sin C = 3, then cos A + cos B + cos C is equal to ______.
In a ΔPQR, if 3 sin P + 4 cos Q = 6 and 4 sin Q + 3 cos P = 1, then ∠R is equal to ______.
The value of sin 930° is ______.
The value of cos(– 870°) is ______.
The value of `(cos(90^circ + θ) sec(-θ)tan(180^circ - θ))/(sec(360^circ - θ)sin(180^circ + θ)cot(90^circ - θ))` is ______.
The value of sin 150° cos 120° + cos 330° sin 660° is ______.
cos2 5° + cos2 10° + cos2 15° + .... + cos2 85° + cos2 90° is equal to ______.
cos 1°. cos 2°. cos 3° ...... cos 179° = ______.
