Finding the area of ​​an ellipse: formula and example

Ellipse is a geometric figure obtained from their circles by an affine transformation.

Area formula

The area of ​​an ellipse (S) is equal to the product of the lengths of its semiaxes and the number π:

S = π * a * b

Note: for calculations the value of a number π rounded up to 3,14.

Example of a problem

Find the area of ​​an ellipse if its semiaxes are 2 cm and 4 cm.

Decision:

We substitute the data known to us according to the conditions of the problem into the formula: S u3,14d 2 * 4 cm * 25,12 cm uXNUMXd XNUMX cm².