How do you find the solution to #9sin^2theta-9sintheta+2=0# if #0<=theta<360#?

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Answer 1 · 2017-01-21T12:52:27

The answers are #S={19.5º , 160.5º, 41.8º, 138.2º}#

Let's factorise the LHS

#9sin^2theta-9sintheta+2=0#

#(3sintheta-1)(3sintheta-2)=0#

Therefore,

#3sintheta-1=0#, #=>#, #sintheta=1/3#

#theta=19.5º , 160.5º#

#3sintheta-2=0#, #=>#, #sintheta=2/3#

#theta=41.8º , 138.2º#