Exercise algebra.manipulation.rational.simplify
Description
simplify a rational expression (with a variable in a divisor)
Derivation
![](http://ideas.cs.uu.nl/images/external.png)
(x^2-9)/(x+3)^2
⇒ algebra.equations.quadratic.nice-factors(x+3)*(x-3)/(x+3)^2
⇒ algebra.equations.rational.cancel-div, clipboard=[condition == (x /= -3)](x-3)/(x+3)