Question

costheta = 1+a^2/1-a^2,| a | does not equal to 1 is this possible?​

Answer 1

Answer:

We have sinθ−cosθ=mina∈R(1,a2−6a+10)

Since a2−6a+11=(a−3)2+2>2 for all a

⟹a2−6a+10>1

∴sinθ−cosθ=1    ............ min value

⇒sin(θ−4π)=21=sin4π

⇒θ−4π=nπ+(−1)n4π

∴θ=nπ+(−1)n4π+4π, where n∈Z