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If triangleABC is a right triangle and i...

If `triangleABC` is a right triangle and if `angleA=pi/2`, then prove that
(i) `cos^(2) B+cos^(2)C=1`
(ii) `sin^(2) B+sin^(2) C=1`
`cos B-cos C=-1+2 sqrt2 cos""B/2sin ""C/2`

Text Solution

Verified by Experts

The correct Answer is:
`-sqrt2 sin ((B-C))/(2)`
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