牛顿法

求 的解

# (x - 3)** 3 = 0

def f(x):
    return (x - 3)**3

def fd(x):
    return 3 * (x - 3)**2

def newtonMethod(n, assum):
    time = n
    x = assum
    A = f(x)
    B = fd(x)
    if f(x) == 0.0:
        return time, x
    else:
        Next = x - A / B

    if A - f(Next) < 1e-6:
        print('meet f(x) = 0, x = %s', str(Next))
    else:
        return newtonMethod(n + 1, Next)

newtonMethod(0, 4.0)