How do you find the solution to $2sin^2theta+sintheta-1=0$ if $0<=theta<360$ ?

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Answer 1 · 2016-12-23T06:57:14

The solutions are $S={30º,150º,270º}$

The equation is $2sin^2theta+sintheta-1=0$

We can factorise the LHS

$(2sintheta-1)(sintheta+1)=0$

Therefore,

$sintheta=-1$ , $=>$ , $theta=270º$

$sintheta=1/2$ , $=>$ , $theta=30º, 150º$

How do you find the solution to 2sin^2theta+sintheta-1=02sin^2theta+sintheta-1=0 if 0<=theta<3600<=theta<360?