sinA*cosB/(cosAsinB)=（√2c-b）/b,根据正弦定理,sinC/sinB=c/b,（√2c-b）/b=√2sinC/sinB-1,sinA*cosB/(cosAsinB)=√2sinC/sinB-1,sinA*cosB=√2sinC*cosA-cosAsinB,sin(A+B)=√2sinC*cosA,A+B=180°-C,sin(A+B)=...