Advertisements
Advertisements
प्रश्न
Prove that cos(30° + x) = `(sqrt(3) cos x - sin x)/2`
Advertisements
उत्तर
cos(30° + x) = `(sqrt(3) cos x - sin x)/2`
cos(30° + x) = cos 30°. cos x – sin 30° sin x
= `sqrt(3)/2 cos x - 1/2 sin x`
cos(30° + x) = `(sqrt(3)cosx- sinx)/2`
APPEARS IN
संबंधित प्रश्न
Find the values of sin(480°)
Find the values of cot(660°)
Find the values of `tan ((19pi)/3)`
Find the value of the trigonometric functions for the following:
cos θ = `- 2/3`, θ lies in the IV quadrant
Find the value of cos 105°.
Prove that cos(π + θ) = − cos θ
Prove that sin(30° + θ) + cos(60° + θ) = cos θ
Prove that cos(A + B) cos(A – B) = cos2A – sin2B = cos2B – sin2A
Show that tan(45° − A) = `(1 - tan "A")/(1 + tan "A")`
Prove that (1 + tan 1°)(1 + tan 2°)(1 + tan 3°) ..... (1 + tan 44°) is a multiple of 4
Prove that `tan (pi/4 + theta) - tan(pi/4 - theta)` = 2 tan 2θ
Show that `cot(7 1^circ/2) = sqrt(2) + sqrt(3) + sqrt(4) + sqrt(6)`
Express the following as a sum or difference
sin 35° cos 28°
Express the following as a sum or difference
sin 5θ sin 4θ
Express the following as a product
sin 50° + sin 40°
Prove that cos(30° – A) cos(30° + A) + cos(45° – A) cos(45° + A) = `cos 2"A" + 1/4`
Show that cot(A + 15°) – tan(A – 15°) = `(4cos2"A")/(1 + 2 sin2"A")`
If A + B + C = 180◦, prove that sin 2A + sin 2B + sin 2C = 4 sin A sin B sin C
If A + B + C = 180°, prove that sin A + sin B + sin C = `4 cos "A"/2 cos "B"/2 cos "C"/2`
If x + y + z = xyz, then prove that `(2x)/(1 - x^2) + (2y)/(1 - y^2) + (2z)/(1 - z^2) = (2x)/(1 - x^2) (2y)/(1 - y^2) (2z)/(1 - z^2)`
