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In a DeltaABC, if a=13,b =14, c =15, the...

In a `DeltaABC`, if a=13,b =14, c =15, then `sinA/2=`

A

`1/(sqrt5)`

B

`2/(sqrt5)`

C

`3/(sqrt5)`

D

`4/(sqrt5)`

Text Solution

Verified by Experts

We have, a = 13, b = 14 and c = 15.
`therefore2s =a+ b + c = 42 rArr a = 21.`
Hence, `sinA/2=(sqrt((21-14)(21-15)))/(14xx15)=sqrt((7xx6)/(14xx15))=1/(sqrt5)`
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