Final answer:
The given expression in terms of x and y only is sin(tan^(-1)((x+y)/(1-xy))).
Step-by-step explanation:
To write the given expression in terms of x and y only, we need to use the trigonometric identities.
Let's start by using the identity: tan^(-1)(x) + tan^(-1)(y) = tan^(-1)((x+y)/(1-xy)).
Substituting this identity into the expression sin(tan^(-1)(x) + tan^(-1)(y)), we get sin(tan^(-1)((x+y)/(1-xy))).
Therefore, the given expression in terms of x and y only is sin(tan^(-1)((x+y)/(1-xy))).