p(x)=ax^3+bx^2+cx+d

a = 1 (slider from -5 to 5, step 0.1)
b = -2 (slider from -5 to 5, step 0.1)
c = -3 (slider from -5 to 5, step 0.1)
d = 2 (slider from -5 to 5, step 0.1)
p(x) = a * x^(3.0) + b * x^(2.0) + c * x + d
texto2: "p(x)=" + p
g = Derivative(p)
texto3: "p'(x) = " + g