Advertisements
Advertisements
प्रश्न
Express the following as the product of sine and cosine.
sin A + sin 2A
Advertisements
उत्तर
sin A + sin 2A = 2 sin`(("A + 2A")/2) cos (("A - 2A")/2)` ...`[∵ sin "C" + sin "D" = sin (("C + D")/2) cos (("C - D")/2)]`
= 2 sin `"3A"/2` cos `"A"/2` ...[∵ cos(-θ) = cos θ]
APPEARS IN
संबंधित प्रश्न
Prove that:
Show that:
sin A sin (B − C) + sin B sin (C − A) + sin C sin (A − B) = 0
Prove that:
\[\tan x \tan \left( \frac{\pi}{3} - x \right) \tan \left( \frac{\pi}{3} + x \right) = \tan 3x\]
Prove that:
Prove that:
`sin A + sin 2A + sin 4A + sin 5A = 4 cos (A/2) cos((3A)/2)sin3A`
Prove that:
Prove that:
Express the following as the product of sine and cosine.
cos 2A + cos 4A
Prove that:
tan 20° tan 40° tan 80° = `sqrt3`.
If cos A + cos B = `1/2` and sin A + sin B = `1/4`, prove that tan `(("A + B")/2) = 1/2`
