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If A, B and C are interior angles of a t...

If A, B and C are interior angles of a triangle ABC, then show that `"sin"((B+C)/2)=cosA/2` .

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  3. If A, B and C are interior angles of a triangle ABC, then show that "s...

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  9. Write the maximum and minimum values of sintheta .

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  10. Write the maximum and minimum values of costheta .

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  11. What is the maximum value of 1/(sectheta) ?

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  12. What is the maximum value of 1/(cos ec \ theta)?

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  13. If tantheta=4/5, find the value of (costheta-sintheta)/(costheta+sinth...

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  14. If costheta=2/3, find the value of (sectheta-1)/(sectheta+1) .

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  15. If 3cottheta=4,find the value of (4costheta-sintheta)/(2costheta+sinth...

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  20. Write the acute angle theta satisfying sqrt(3)sintheta=costheta .

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