Answer:0.9232
Step-by-step explanation:
Sin(A+B)=56/65 A+B=sin^(-1)56/65 A+B=59.5
SinA=3/5 A=sin^(-1)3/5 A=36.9
Since A+B=59.5 we substitute A=36.9 in the equation
36.9+B=59.5
B=59.5-36.9
B=22.6
CosB=cos22.6=0.9232
