Find the approximated integral value of an equation 1/(x+1) using Midpoint Rule
a = 0 and b = 1
Interval n = 5Solution:Equation is `f(x)=(1)/(x+1)`
`a=0`
`b=1`
`Delta x =(b-a)/n=(1 - 0)/5=0.2`
The value of table for `x`
| `x` |
| `x_0=0` |
| `x_1=0.2` |
| `x_2=0.4` |
| `x_3=0.6` |
| `x_4=0.8` |
| `x_5=1` |
Method-1:Using Midpoint Rule of Riemann Sum
`int f(x) dx=Delta x xx(f((x_0+x_1)/2)+f((x_1+x_2)/2)+f((x_2+x_3)/2)+...+f((x_(n-1)+x_n)/2))`
`int f(x) dx=Delta x xx(f((x_0+x_1)/2)+f((x_1+x_2)/2)+f((x_2+x_3)/2)+f((x_3+x_4)/2)+f((x_4+x_5)/2))`
`=Delta x xx(f((0+0.2)/2)+f((0.2+0.4)/2)+f((0.4+0.6)/2)+f((0.6+0.8)/2)+f((0.8+1)/2))`
`=Delta x xx(f(0.1)+f(0.3)+f(0.5)+f(0.7)+f(0.9))`
`=0.2xx(0.9091+0.7692+0.6667+0.5882+0.5263)`
`=0.2xx(3.4595)`
`=0.6919`
Solution by Midpoint Rule of Riemann Sum is `0.6919`
This material is intended as a summary. Use your textbook for detail explanation.
Any bug, improvement, feedback then