Advertisements
Advertisements
प्रश्न
Choose the correct alternative:
cos 1° + cos 2° + cos 3° + ... + cos 179° =
विकल्प
0
1
−1
89
उत्तर
0
APPEARS IN
संबंधित प्रश्न
Find the values of cot(660°)
Find the values of `tan ((19pi)/3)`
Find the value of cos 105°.
Find the value of tan `(7pi)/12`
Prove that cos(30° + x) = `(sqrt(3) cos x - sin x)/2`
Expand cos(A + B + C). Hence prove that cos A cos B cos C = sin A sin B cos C + sin B sin C cos A + sin C sin A cos B, if A + B + C = `pi/2`
Prove that sin(45° + θ) – sin(45° – θ) = `sqrt(2) sin θ`
Show that tan(45° + A) = `(1 + tan"A")/(1 - tan"A")`
Show that tan(45° − A) = `(1 - tan "A")/(1 + tan "A")`
If tan x = `"n"/("n" + 1)` and tan y = `1/(2"n" + 1)`, find tan(x + y)
Find the value of cos 2A, A lies in the first quadrant, when sin A = `4/5`
If θ is an acute angle, then find `sin (pi/4 - theta/2)`, when sin θ = `1/25`
Prove that (1 + sec 2θ)(1 + sec 4θ) ... (1 + sec 2nθ) = tan 2nθ
Express the following as a sum or difference
sin 4x cos 2x
Express the following as a product
cos 65° + cos 15°
Express the following as a product
sin 50° + sin 40°
If A + B + C = 180°, prove that cos A + cos B − cos C = `- 1 + 4cos "A"/2 cos "B"/2 sin "C"/2`
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 sin2 B + sin2 C = 1
Choose the correct alternative:
`(sin("A" - "B"))/(cos"A" cos"B") + (sin("B" - "C"))/(cos"B" cos"C") + (sin("C" - "A"))/(cos"C" cos"A")` is
