sina=3/5,a∈(0,π/2),求tan2a+根号2cos(a-π/4)

sina=3/5,a∈(0,π/2),求tan2a+根号2cos(a-π/4)

sina=3/5,a∈(0,π/2),说明cosa=4/5
tan2a+根号2cos(a-π/4)=2sinacosa/[(cosa）^2-(sina)^2+cosa+sina=24/7-7/5=169/35
应该没错