Advertisements
Advertisements
प्रश्न
Prove that 2 tan 80° = tan 85° – tan 5°.
Advertisements
उत्तर
Consider tan 80° = tan(85° – 5°)
`= (tan 85° - tan 5°)/(1 + tan 85° tan 5°)`
`= (tan 85° - tan 5°)/(1 + tan 85° tan (90° - 85°))`
`= (tan 85^circ - tan 5^circ)/(1 + tan 85^circ xx cot 85^circ)`
`= (tan 85^circ - tan 5^circ)/(1 + 1)`
`= (tan 85^circ - tan 5^circ)/2`
∴ 2 tan 80° = tan 85° – tan 5°
Hence Proved.
APPEARS IN
संबंधित प्रश्न
Find the value of the following:
cosec 15º
Find the value of the following:
sin (-105°)
Find the value of the following:
sin 76° cos 16° – cos 76° sin 16°
Prove that:
tan 4A tan 3A tan A + tan 3A + tan A – tan 4A = 0
If tan x = `3/4` and `pi < x < (3pi)/2`, then find the value of sin `x/2` and cos `x/2`.
Prove that `2 sin^2 (3pi)/4 + 2 cos^2 pi/4 + 2 sec^2 pi/3` = 10
Find the value of sin 75°.
Find the value of tan 15°.
The value of sin 15° is:
The value of sin (-420°)
