from numpy import arange
import matplotlib.pyplot as ptl


fX="(3**)- (7*(x**2)+14*x)-6"
rango = arange (0.5, 1, 0.001)
valores =[]

for x in rsngo:
    y=eval(fx)
    valores.append(y)
plt.plot(rango.valore)
plt.grid(axis=´buth´)
ptl.show()
