Sail E0 Webinar
Question


  3tanθ + cotθ = 5cosecθ. Solve for θ, 0θ90.


__
Options:
Answer: Option A
:

3sinθcosθ + cosθsinθ5sinθ
3sin2θ + cos2θsinθcosθ=5sinθ
3sin2θ+cos2θ=5cosθ
3(1 - cos2θ) + cos2θ = 5 cosθ
2cos2θ + 5cosθ - 3 = 0 
2cosθ  [cosθ + 3] - 1(cosθ + 3) = 0
(cosθ + 3) (2cosθ - 1) = 0
cosθ = -3     or     cosθ = 12
Note that cosθ = -3  is not possible as 1cosθ1                     
 Thus, θ = 60



Was this answer helpful ?
Next Question

Submit Solution

Your email address will not be published. Required fields are marked *

Latest Videos

Latest Test Papers