Advertisements
Advertisements
प्रश्न
If tan x = `3/4` and `pi < x < (3pi)/2`, then find the value of sin `x/2` and cos `x/2`.
उत्तर
Given tan x = `3/4` and `pi < x < (3pi)/2`
Since x lies in the III quadrant, only tan and its reciprocal are positive.
sin x = `(-3)/5`, cos x = `(-4)/5`.
Now, sin `x/2 = sqrt((1 - cos x)/2) = sqrt(((1 - (-4/5))/2)`
`= sqrt((1 + 4/5)/2)`
`= sqrt(9/10)`
`= 3/sqrt10`
`cos x/2 = sqrt((1 + cos x)/2) = sqrt((1 + 4/5)/2)`
`= sqrt((1 - 4/5)/2) = sqrt(1/10) = 1/sqrt10`
APPEARS IN
संबंधित प्रश्न
Find the value of the following:
sin (-105°)
Find the value of the following:
cos 70° cos 10° – sin 70° sin 10°
Find the value of the following:
cos2 15° – sin2 15°
If sin A = `3/5`, 0 < A < `pi/2` and cos B = `(-12)/13`, π < B < `(3pi)/2`, find the values of the following:
- cos(A + B)
- sin(A – B)
- tan(A – B)
If cot α = `1/2`, sec β = `(-5)/3`, where π < α < `(3pi)/2 and pi/2` < β < π, find the value of tan(α + β). State the quadrant in which α + β terminates.
Prove that:
tan 4A tan 3A tan A + tan 3A + tan A – tan 4A = 0
If tan θ = 3 find tan 3θ
Find the value of tan `pi/8`.
The value of sin 15° is:
The value of sec A sin(270° + A) is: