if tan theta=7/24theta is in 2nd quadrant then find tan theta /2 and sin theta/2
Answers
Given :-
tan theta = 7/24
Here we take x place of theta .
& theta lies in 2nd quadrant .
Have To Find Out :-
Value of tan (theta/2) & Sin (theta/2)
Using Properties :-
tanx = 2tan (x/2) / 1 - tan²(x/2)
Explanation :-
From the property -
7/24 = 2tan (x/2) / 1 - tan²(x/2)
On Doing cross multiplication
7 - 7tan²(x/2) = 48 tan (x/2)
7tan²(x/2) + 48tan (x/2) - 7 = 0
7tan²(x/2) + 49tan(x/2) - tan(x/2) - 7 = 0
7tan(x/2) {tan(x/2) + 7} - {tan(x/2) + 7} = 0
{7tan(x/2) - 1} {tan(x/2) + 7} = 0
So , tan(theta/2) = 1/7 & -7
-7 not possible .
From the value of tan(theta/2) ,
perpendicular = 1 , base = 7
Hypotenuse = √1² + 7² = √50 = 5√2
Then ,
Sin(theta/2) = P/H = 1 /5√2