SQL Database Design For Developers at php[tek] 2024
010 applications of integral calculus
1. Applications of Integral Calculus
The Area between Two Curves
Find the area between and from x = 0 to x = 1.
To get the height representative rectangle in the Figure, subtract the y-coordinate of its bottom from the y-
coordinate of its top. Its base is infinitesimal dx. So, because area equals height times base,
[( ) ]
Now, just add up the areas of all the rectangles from 0 to 1 by integrating:
∫ [( ) ]
[ ]
( ) ( )
Solids of Revolution: Circular Disk Method
Find the volume of the solid – between x = 2 and x = 3 – generated by rotating the curve y = ex about the
x-axis.
2. Each cross-section is a circle with a radius of ex. So, its area is given by the formula for the area
Plugging ex into r gives us: ( ) .
Adding up the volumes from 2 to 3 and integrating:
∫
[ ]
[ ]
Solids of Revolution: Circular Ring Method
Take the area bounded by and √ , and generate a solid by revolving that area about the x-
axis.