2 5*(a - 2) - 10*a
5*(a - 1*2)^2 - 10*a
/ ___\ / ___\ 1*\a + -3 + \/ 5 /*\a + -3 - \/ 5 /
(1*(a - (3 + sqrt(5))))*(a - (3 - sqrt(5)))
2 20 - 30*a + 5*a
20 - 30*a + 5*a^2
20.0*(-1 + 0.5*a)^2 - 10.0*a
/ 2 \ 5*\(-2 + a) - 2*a/
5*((-2 + a)^2 - 2*a)