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In DeltaABC, prove that: a(cos^(2)C/3-...

In `DeltaABC`, prove that:
`a(cos^(2)C/3-cos^(2)B/2)=(b-c).cos^(2)A/2`

Text Solution

Verified by Experts

LHS= `a(cos^(2)C/2-cos^(2)B/2)`
`=a[(s(s-c))/(ab)-(s(s-b))/(ac)]`
`=a.s/a[(s-c)/(b)-(s-b)/( C)]`
`
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