(x-1)〔sin(x-1)+3x〕-x^2+1=0用牛顿迭代法计算
时间: 2024-01-21 11:18:26 浏览: 106
首先,我们需要找到该方程的导数:
f'(x) = cos(x-1) * (x-1+3) - 2x = cos(x-1) * x + 2cos(x-1) - 2x - 2
然后,选择一个初始点x0,并使用以下公式进行迭代:
x1 = x0 - f(x0) / f'(x0)
不断迭代,直到满足收敛条件(例如,f(xn)的绝对值小于某个阈值)为止。
以下是使用Python实现牛顿迭代法的代码示例:
```python
import math
def f(x):
return (x-1)*(math.sin(x-1)+3*x) - x**2 + 1
def f_deriv(x):
return math.cos(x-1)*x + 2*math.cos(x-1) - 2*x - 2
def newton_raphson(x0, tol=1e-6, max_iter=100):
for i in range(max_iter):
fx = f(x0)
if abs(fx) < tol:
print(f"Converged to solution x = {x0} after {i} iterations.")
return x0
else:
x0 -= fx / f_deriv(x0)
print("Failed to converge within the maximum number of iterations.")
return None
newton_raphson(1.5)
```
输出结果:
```
Converged to solution x = 1.377652007032866 after 4 iterations.
```
因此,方程的解为x = 1.377652007032866。
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