Q. If tan A=2 , A lies in the 3rd quadrant
Find sin A + Cos A
ARE KOI TO BATAO.............!!!!
Answers
Answered by
10
Answer:
I don't sis sry
Step-by-step explanation:
pls follow me
Answered by
4
Answer:
Here given sinA=–4/5 and A lie in 3nd quadrant, i.e π<A<3π/2,lt means in 3nd quadrant cosA, sinA is negative and tanA is positive.
If sinA =–4/5
then,
cosA=-√(1-sin²A)=-√(1- 16/25) =-√(9/25) =-3/5
So,1-cosA=2sin²(A/2)
=>1- (-3/5)=2.sin²(A/2)
=>(1+ 3/5)=2sin²(A/2)
=>8/5=2sin²(A/2)
=>4/5 =sin²(A/2)
=>√(4/5)=sinA/2
=2/√5=sinA/2
cosec(A/2)=√5/2
Because π/2<A/2<3π/4 in 2nd quadrant.
Similarly,
sinA=2.sin(A/2).cos(A/2)
=>-4/5=2×2/√5 .cos(A/2)
-1/√5=cos(A/2)
Therefore,
tan(A/2) =sin(A/2)/cos(A/2)=2/√5 /(-1/√5) =-2
Step-by-step explanation:
Hope it's helpful to you ☺️ tanve
Similar questions