1.

In `DeltaABC`, prove that: `asin(B-C)+bsin(C-A)+csinA-B)=0`

Answer» 1st term =`asin(B-C)`
`=ksinA.sin(B-C)`
`=ksin{180^(@)-(B+C)}sin(B-C)`
`ksin(B+C).sin(B-C)`
`=ksin^(2)B-sin^(2)C`
Similarly,
2nd term `=k(sin^(2)C-sin^(2)A)`
3rd term `=k(sin^(2)A-sin^(2)B)`
Now L.H.S. `=asin(B-C)+bsin(C-a)+csin(A-B)`
`=k(sin^(2)B-sin^(2)C)+k(sin^(2)C-sin^(2)A)+k(sin^(2)A-sin^(2)B)`
`ksin^(2)B-ksin^(2)C-ksin^(2)A+ksin^(2)A-ksin^(2)B` =0 = RHS Hence Proved.


Discussion

No Comment Found