Question

Many practical applications require calculations of area. Some of these calculations are straightforward, but others are more difficult, and it turns out that the idea of the definite integral can help us with the more difficult cases. Let’s start with some familiar shapes. What is the area of a rectangle of length l and width w?

Answer 1

L*W

Explanation:

As we Know tha area of a rectangle is Leght*witdth so in this case will be L*W but lets prove it by calculating the integral:

Area= L*W=
`\int\limits^w_0 F{x} \, dx =\int\limits^w_0 L*w({x}) \, dx`

So as the integral of a constant is the constant multiplied by the integration variable x.

The integral becomes: L*W(x) where W(x) in this case is W= L*W

Good luck!