Given : $$cosec\theta=\frac{17}{8}$$
=> $$sin\theta=\frac{8}{17}$$
Using, $$sin^2\theta+cos^2\theta=1$$
=> $$cos^2\theta=1-(\frac{8}{17})^2$$
=> $$cos^2\theta=1-\frac{64}{289}=\frac{225}{289}$$
=> $$cos\theta=\sqrt{\frac{225}{289}}=\frac{15}{17}$$
=> Ans - (B)
Create a FREE account and get: