Linearization.

Exponential and trigonometric linearization are implemented via:

• EXPLIN: $e^x e^y \rightarrow e^{x+y}$ and for integral powers (e^x)ⁿ=e^nx
• TRIGLIN: $\sin(x)\sin(y)=\frac{1}{2} (\cos(x-y)-\cos(x+y))$ and similar identities, $\sin(x)^n$ and $\cos(x)^n$ for n integer