Question 350607
{{{cos(theta)=-sqrt(5)/3}}}
{{{sin^2(theta)+cos^2(theta)=1}}}
{{{sin^2(theta)+5/9=1}}}
{{{sin^2(theta)=4/9}}}
{{{sin(theta)=0 +- 2/3}}}
Since the restriction on {{{theta}}} is {{{180 < theta < 270}}}, then 
{{{sin(theta)=-2/3}}}
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Use the trig identity,
{{{sin(2*theta)=2sin(theta)cos(theta)}}}
{{{sin(2*theta)=2(-2/3)(-sqrt(5)/3))}}}
{{{highlight(sin(2*theta)=(4/9)sqrt(5))}}}