Question 1155504
{{{2sin^2(x)+sinx-1=0}}}

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{{{(2sin(x)-1)(sin(x)+1)=0}}}

Either 
{{{2sin(x)=1}}}
{{{sin(x)=1/2}}}
{{{system(x=pi/6,or,x=5pi/6)}}}
OR
{{{sin(x)=-1}}}
{{{x=3pi/2}}}