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Find the value of tan A/2, if area of De...

Find the value of tan A/2, if area of `Delta ABC is a^(2) -(b-c)^(2).`

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`Delta = (a + b - c) (a - b + c)`
`rArr Delta^(2) = [2 (s -b) 2(s -c)]^(2)`
or `s(s - a) (s -b) (s-c) = 16 (s-b)^(2) (s-c)^(2)`
or `((s-b) (s-c))/(s(s-a)) = (1)/(16)`
or `tan.(A)/(2) = (1)/(4)`
`rArr tan^(2)A = (2 tan (A//2))/(1 - tan^(2) (A//2)) = (2(1//4))/(1-(1//16)) = (8)/(15)`
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