Please I need to solve this exercice :
Prove that in any triangular" (ABC) is true the equalisation :
sinA +sinB + sinC=4 cos (A/2) cos(B/2) cos (C/2)
I think it has been solved here: http://www.enotes.com/homework-help/b-c-pi-prove-that-identity-true-sin-sin-b-sin-c-154655
Thanks anon :)
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