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Question
Find the values of `sin (-(11pi)/3)`
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Solution
`sin (-(11pi)/3) = - sin (11pi)/3`
= `- sin 11/3 xx 180`
= `- sin 11/3 xx 360/2`
= `- sin 360^circ (11/6)`
= `- sin 360^circ (2 - 1/6)`
= `- [sin(360^circ xx 2) - 360^circ/6]`
= – (– sin 60°)
= `sqrt(3)/2`
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