sin 3theta-cos 3theta greater than zero then theta lies in

Asked by mujjuashu0362 | 17th May, 2022, 12:50: PM

Expert Answer:

sin cubed straight theta minus cos cubed straight theta greater than 0
left parenthesis sinθ minus cosθ right parenthesis left parenthesis sin squared straight theta plus sinθcosθ plus cos squared straight theta right parenthesis greater than 0
left parenthesis sinθ minus cosθ right parenthesis left parenthesis 1 plus sinθcosθ right parenthesis greater than 0
left parenthesis sinθ minus cosθ right parenthesis greater than 0 space and space left parenthesis 1 plus sinθcosθ right parenthesis greater than 0 space space OR space left parenthesis sinθ minus cosθ right parenthesis less than 0 space and space left parenthesis 1 plus sinθcosθ right parenthesis less than 0
sinθ greater than cosθ space and space sinθcosθ greater than negative 1 space space OR space space sinθ less than cosθ space and space sinθcosθ less than negative 1
tanθ greater than 1 space
Therefore comma space straight theta element of open parentheses straight pi over 4 comma straight pi over 2 close parentheses union open parentheses fraction numerator 5 straight pi over denominator 4 end fraction comma fraction numerator 3 straight pi over denominator 2 end fraction close parentheses

Answered by Renu Varma | 20th May, 2022, 04:19: PM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.