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+# More integral
+
+### Newton-Cotes Algorithms for Equations
+### Adaptive Quadrature
+
+
+## Problems
+
+## Numerical Integration to Compute Work
+In physics we've learned that work is computed
+$$
+Work = force * distance
+$$
+This can be written in int's integral form:
+$$
+W = \int{F(x)dx}
+$$
+If F(x) is easy to integrate, we could solve this problem analytically. However, a realistic problem the force may not be available to you as a function, but rather, tabulated data. Suppose some measurements were take of when a weighted box was pulled with a wire. If we data of the force on the wire and the angle of the wire from the horizontal plane.
+
+| x (ft) | F(x) (lb) | θ (rad) | F(x) cos θ |
+| ------ | --------- | ------- | ---------- |
+| 0 | 0.0 | 0.50 | 0.0000 |
+| 5 | 9.0 | 1.40 | 1.5297 |
+| 10 | 13.0 | 0.75 | 9.5120 |
+| 15 | 14.0 | 0.90 | 8.7025 |
+| 20 | 10.5 | 1.30 | 2.8087 |
+| 25 | 12.0 | 1.48 | 1.0881 |
+| 30 | 5.0 | 1.50 | 0.3537 |
+| | | | |
+Use the trapezoidal rule to compute the work done on the box.
+
+## Implementing the Composite Trapezoidal Rule
+
+Implement a Python function to approximate integrals using the trapezoidal rule.
+
+```python
+import numpy as np
+
+def trapz(f, a, b, n):
+ x = np.linspace(a, b, n+1)
+ y = f(x)
+ h = (b - a) / n
+ return h * (0.5*y[0] + y[1:-1].sum() + 0.5*y[-1])
+
+# Example tests
+f1 = np.sin
+I_true1 = 2.0 # ∫_0^π sin(x) dx
+for n in [4, 8, 16, 32]:
+ print(n, trapz(f1, 0, np.pi, n))
+```
+
+Compare the results for increasing $n$ and observe how the error decreases with $O(h^2$).