Sin(arcsin(4/5)+arctan(12/5))
=Sin(arcsin(4/5)+arc cot(5/12))
=Sin(arcsin(4/5)+arc csc(sqrt(1+(5/12)^2)
=Sin(arcsin(4/5)+arc csc(13/12))
=Sin(arcsin(4/5)+arc sin(12/13))
=Sin(arcsin((4/5)xxsqrt(1-(12/13)^2)+(12/13)xxsqrt(1-(4/5)^2))
=(4/5xx5/13)+(12/13xx3/5)=56/65