pls guys do fast pls
its urgent
if tan x=3/4, pie<x<3 pie/2
find the. value of
sin x/2,cosx/2 and tan x/2
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Heya,
We know that,
Sec²x = 1+tan²x
Sec²x = 1+(3/4)²
Sec²x = 1+(9/16)
Sec²x = 25/16
Secx = +- √25/16
Secx = +- 5/4
Since, π < x < 3π/2, It belongs to III quadrant in which Secx is negative
So,
Secx = -5/4
Cosx = -4/5
We have to know values of x/2
π < x < 3π/2
then,
π/2 < x/2 < 3π/2x2
π/2 < x/2 < 3π/4
So, x/2 belongs to II quadrant
So, Sinx/2 > 0, Cosx/2 < 0
1) 2Sin²x/2 = (1-cosx) = (1+4/5) = 9/5
Sin²x/2 = 9/10
Sinx/2 = +- √9/10
Sinx/2 = +- 3/√10
Since x/2 belongs II quad, Sinx/2 > 0
Sinx/2 = 3/√10
2) 2Cos²x/2 = 1+Cosx = 1-4/5 = 1/5
Cos²x/2 = 1/10
Cosx/2 = +- 1/√10
Since x/2 belongs to II quad, Cosx/2 is negative
Cos x/2 = -1/√10
3) tanx/2 = Sinx/2 / Cos x/2
= 3/√10 / -1/√10
= -3
Since x/2 belongs to II quad, tan x/2 is negative
tanx/2 = -(-3)
tanx/2 = 3
HOPE IT HELPS:-))
We know that,
Sec²x = 1+tan²x
Sec²x = 1+(3/4)²
Sec²x = 1+(9/16)
Sec²x = 25/16
Secx = +- √25/16
Secx = +- 5/4
Since, π < x < 3π/2, It belongs to III quadrant in which Secx is negative
So,
Secx = -5/4
Cosx = -4/5
We have to know values of x/2
π < x < 3π/2
then,
π/2 < x/2 < 3π/2x2
π/2 < x/2 < 3π/4
So, x/2 belongs to II quadrant
So, Sinx/2 > 0, Cosx/2 < 0
1) 2Sin²x/2 = (1-cosx) = (1+4/5) = 9/5
Sin²x/2 = 9/10
Sinx/2 = +- √9/10
Sinx/2 = +- 3/√10
Since x/2 belongs II quad, Sinx/2 > 0
Sinx/2 = 3/√10
2) 2Cos²x/2 = 1+Cosx = 1-4/5 = 1/5
Cos²x/2 = 1/10
Cosx/2 = +- 1/√10
Since x/2 belongs to II quad, Cosx/2 is negative
Cos x/2 = -1/√10
3) tanx/2 = Sinx/2 / Cos x/2
= 3/√10 / -1/√10
= -3
Since x/2 belongs to II quad, tan x/2 is negative
tanx/2 = -(-3)
tanx/2 = 3
HOPE IT HELPS:-))
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