If π4<θ<π2, then write the value of √1−sin 2θ
Since π4<θ<π2
⇒ θ lies in the first quadrant 1st quadrant
Now,
√1−sin 2θ=√sin2 θ+cos2 θ−2 sin θ cos θ=√(sin θ−cos θ)2=sin θ−cos θ
(a) If sinA=1213 and sinB=45, where π2<A<π and 0<B<π2, find the following: (i) sin(A+B) (ii) cos(A+B) (b) If sinA= 35, cosB=1213, where A and B both lie in second quadrant, find the value of sin(A+B).
If in a △ABC, a2 cos2A=b2+c2 then