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If sin theta = a/(b+c) then show that co...

If `sin theta = a/(b+c)` then show that `cos theta = (2sqrt(bc))/(b+c) cos ((A)/(2))`

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The correct Answer is:
`(2 sqrt(ab))/(a+b) . cos"" (C )/(2)`
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VIKRAM PUBLICATION ( ANDHRA PUBLICATION)-PROPERTIES OF TRIANGLES-TEXTUAL EXERCISES ( EXERCISE - 10(a) ) III.
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  2. b-c // b+c cot A/2 + b+c // b-c tan A/2 = 2 cosec (B-C)అని చూపండి.

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  4. If a=(b+c)costheta, " then prove that" sintheta=(2sqrt(bc))/(b+c)cos((...

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  9. If cos ^(2) A + cos ^(2) B = cos ^(2) C = 1 then show that Delta A...

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  11. In Delta ABC , if cot "" (A)/(2) , cot "" ( B)/(2) , cot "" (C )/(2...

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