sin(2A+B)+sin(2A+3B)
=sin(2A+2B-B)+sin(2A+2B+B)
=2sin(2A+2B)cosB
又sin(2A+2B)=2sin(A+B)cos(A+B)
因为sin(A+B)=1
所以cos(A+B)=0
则sin(2A+2B)=0
故sin(2A+B)+sin(2A+3B)=0
sin(a+b)=1,则sin(2a+b)+sin(2a+3b)=
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