# Delta sine

Let $\mathbb{T}$ be a time scale, let $s \in \mathbb{T}$, and let $\mu p^2 \colon \mathbb{T} \rightarrow \mathbb{R}$ be a regressive function. We define the trigonometric function $\sin_p \colon \mathbb{T} \times \mathbb{T} \rightarrow \mathbb{R}$ by $$\sin_p(t,s;\mathbb{T})=\dfrac{e_{ip}(t,s;\mathbb{T})-e_{-ip}(t,s;\mathbb{T})}{2i}$$
 $\mathbb{T}$ $\sin$$_p(t,s)=$ $\mathbb{R}$ $\mathbb{Z}$ $\dfrac{\displaystyle\prod_{k=t_0}^{t-1}1+ip(k) - \displaystyle\prod_{k=t_0}^{t-1}1-ip(k)}{2i}$ $h\mathbb{Z}$ $\mathbb{Z}^2$ $\overline{q^{\mathbb{Z}}}, q > 1$ $\overline{q^{\mathbb{Z}}}, q < 1$ $\mathbb{H}$
 $\Delta$-special functions on time scales $\cos_p$ $\cosh_p$ $e_p$ $g_k$ $h_k$ $\sin_p$ $\sinh_p$