Advertisements
Advertisements
Question
Find the value of:
sin 15°
Advertisements
Solution
sin 15°
= sin (45° – 30°)
= sin 45° cos 30° – cos 45° sin 30°
= `(1/sqrt(2))(sqrt(3)/2) - (1/sqrt(2))(1/2)`
= `(sqrt(3) - 1)/(2sqrt(2)`
Notes
Answer given in the textbook is `(sqrt(3) + 1)/(2sqrt(2)`. However, as per our calculation it is `(sqrt(3) - 1)/(2sqrt(2)`.
APPEARS IN
RELATED QUESTIONS
Find the values of:
cos 75°
Find the values of:
tan 105°
Find the value of sin 690°.
Find the value of :
cos 315°
Find the value of :
cos (600°)
Find the value of :
tan 225°
Find the value of :
tan (– 690°)
Find the value of :
sec 240°
Find the value of:
sec (–855°)
Find the value of :
cosec 780°
Prove the following:
`(sin^3(pi + x)sec^2(pi - x)tan(2pi - x))/(cos^2(pi/2 + x)sin(pi - x)"cosec"^2 - x)` = tan3x
Select the correct option from the given alternatives :
If sin θ = n sin (θ + 2α), then tan (θ + α) is equal to
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 20° sin 40° sin 80° = `sqrt(3)/8`
Prove the following:
`tan pi/8 = sqrt(2) - 1`
Prove the following:
sin47° + sin61° − sin11° − sin25° = cos7°
If a = sin 175°+ cos 175°, then ______.
If f(x) = `(2"x" + 3)/(3"x" - 2)`, `"x" ≠ 2/3`, then the function fof is ____________.
`(1 - 2[cos 60^circ - cos 80^circ])/(2 sin 10^circ)` = ______.
The value of sin(– 1125°) is ______.
The value of `cos((41π)/4)` is ______.
The value of `cos π/8 + cos (3π)/8 + cos (5π)/8 + cos (7π)/8` is ______.
Find the value of `cos ((29 π)/3)`.
The value of `cos^2 π/16 + cos^2 (3π)/16 + cos^2 (5π)/16 + cos^2 (7π)/16` is ______.
cos 1° + cos 2° + cos 3° + ... + cos 180° is equal to ______.
The value of cos (270° + θ) cos (90° – θ) – sin (270° – θ) cos θ is ______.
The value of the expression sin6 θ + cos6 θ + 3 sin2 θ . cos2 θ is ______.
The value of sin 930° is ______.
The value of tan 315° cot(– 405°) + cot 495° tan (– 585°).
The value of `2 sin^2 π/6 + "cosec"^2 (7π)/6 cos^2 π/3` is ______.
cos2 5° + cos2 10° + cos2 15° + .... + cos2 85° + cos2 90° is equal to ______.
