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In triangle A B C , prove that sin(A/2)...

In triangle `A B C ,` prove that `sin(A/2)+sin(B/2)+sin(C/2)lt=3/2dot` Hence, deduce that `cos((pi+A)/4)cos((pi+B)/4)cos((pi+C)/4)lt=1/8`

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CENGAGE ENGLISH-TRIGONOMETRIC FUNCTIONS-All Questions
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