2 (2 - c) - c*(c - 4)
(2 - c)^2 - c*(c - 1*4)
4
1
4.0*(1 - 0.5*c)^2 - c*(-4.0 + c)
2 2 (2 - c) - c + 4*c
(2 - c)^2 - c^2 + 4*c