微积分I(标准路径) · 免费预览
§5.6 Numerical integration (continued)
当被积函数不存在初等代数原函数,因而无法使用微积分第一基本定理时,我们如何准确计算诸如 $\int_0^1 e^{-x^2} \, dx$ 这样的定积分?是否有一些方法可以在黎曼和中不使用极大的 $n$ 值的情况下得到精确的估计?
1. Overall observations regarding
Overall observations regarding
2. Summary
Summary
3. Endpoint sums depend only on endpoints
Three functions , , all satisfy value at and value at . Their one panel sums and are
4. Simpson lands exactly on quadratics
For the test functions, for and for , matching the exact integrals and , while the third function's exact value exceeds its . The explanation is
5. Classifying a mystery function
For an unknown monotone, fixed concavity function on , we have , with midpoint above trapezoid . The function is
6. Why one integral resists everything
The integral cannot be evaluated exactly with the chapter's tools because
7. Dam flow through sixty seconds
Flow rates CFS are recorded every ten seconds. With , , and , the best volume estimate is
8. Simpson value for the first test function
With and for the test function , compute Simpson's as a fraction.
9. Best estimate for the mystery integral
For the unknown function with , , , and , Simpson's estimate is the best available. Compute , rounded to two decimals.
10. Midpoint value for the second test function
The test function satisfies . Compute the one panel midpoint estimate for as a decimal.
11. Dam volume by midpoint
Using midpoint samples at seconds with panel width , compute for the dam flow integral in cubic feet.
12. Exactness class of Simpson's rule
Simpson's rule integrates linear functions and quadratic functions exactly.