If cosecθ = 2, show that
We have, cosecθ = 2 = 1/sinθ
→ sinθ = k/(2k) = BC/AB (For some value of k)
By Pythagoras theorem, (hypotenuse)2 = (perpendicular)2 + (base)2
∴AB2 = BC2 + AC2
= (2k)2 = (k)2 + AC2
= 4k2 = k2 + AC2
= AC2 = 3k2
→ AC = k√3
∴ cosθ = AC/AB = (k√3)/(2k) = √3/2
cotθ = cosθ /sinθ = AC/BC = √3
consider the LHS,
LHS = cotθ + = √3 +
= √ 3 +
=
=
=
= 2
= RHS
HENCE PROVED