- $\sin^2x={1 \over 2}(1-\cos 2x)$
- $\cos^2x={1 \over 2}(1+\cos 2x)$
-- $\sin 2x = 2 \sin x \cos x
+- $\sin 2x = 2 \sin x \cos x$
+
+### Partial fractions
+
+On CAS: Action $\rightarrow$ Transformation $\rightarrow$ `expand/combine`
## Applications of antidifferentiation