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Prove that 3 sin ""pi/6 sec ""pi/3 -4 ...

Prove that
`3 sin ""pi/6 sec ""pi/3 -4 sin ""(5pi)/(6) cot"" (pi)/(4) = 3 -4 xx 1/2 =1=R.H.S.`

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The correct Answer is:
`=2-4 xx 1/2 =1 =R.H.S.`
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