Advertisements
Advertisements
प्रश्न
Express the following as a sum or difference
sin 5θ sin 4θ
Advertisements
उत्तर
sin 5θ sin 4θ
We know
sin A sin B = `1/2`[cos(A – B) – cos(A + B)]
Take A = 5θ, B = 4θ
sin 5θ . sin 4θ = `1/2`[cos(5θ – 4θ) – cos(5θ + 4θ)]
sin 5θ . sin 4θ = `1/2`[cos θ – cos 9θ]
APPEARS IN
संबंधित प्रश्न
Find the values of sin (– 1110°)
`(5/7, (2sqrt(6))/7)` is a point on the terminal side of an angle θ in standard position. Determine the six trigonometric function values of angle θ
Find the value of the trigonometric functions for the following:
cos θ = `- 1/2`, θ lies in the III quadrant
Prove that cos(30° + x) = `(sqrt(3) cos x - sin x)/2`
Find a quadratic equation whose roots are sin 15° and cos 15°
Prove that sin(n + 1) θ sin(n – 1) θ + cos(n + 1) θ cos(n – 1)θ = cos 2θ, n ∈ Z
Prove that cos 8θ cos 2θ = cos25θ – sin23θ
Show that cos2 A + cos2 B – 2 cos A cos B cos(A + B) = sin2(A + B)
Find the value of cos 2A, A lies in the first quadrant, when cos A = `15/17`
Prove that sin 4α = `4 tan alpha (1 - tan^2alpha)/(1 + tan^2 alpha)^2`
Show that `cot(7 1^circ/2) = sqrt(2) + sqrt(3) + sqrt(4) + sqrt(6)`
Prove that `32(sqrt(3)) sin pi/48 cos pi/48 cos pi/24 cos pi/12 cos pi/6` = 3
Express the following as a sum or difference
sin 4x cos 2x
Express the following as a sum or difference
cos 5θ cos 2θ
Show that `((cos theta -cos 3theta)(sin 8theta + sin 2theta))/((sin 5theta - sin theta) (cos 4theta - cos 6theta))` = 1
If A + B + C = `pi/2`, prove the following sin 2A + sin 2B + sin 2C = 4 cos A cos B cos C
If ∆ABC is a right triangle and if ∠A = `pi/2` then prove that cos2 B + cos2 C = 1
If ∆ABC is a right triangle and if ∠A = `pi/2` then prove that sin2 B + sin2 C = 1
Choose the correct alternative:
`1/(cos 80^circ) - sqrt(3)/(sin 80^circ)` =
Choose the correct alternative:
If cos 28° + sin 28° = k3, then cos 17° is equal to
