# maximum area

## Length of one side for maximum area of trapezoid (solution by Calculus)

**Problem**

BC of trapezoid ABCD is tangent at any point on circular arc DE whose center is O. Find the length of BC so that the area of ABCD is maximum.

## Length of one side for maximum area of trapezoid (solution by Geometry)

**Problem**

BC of trapezoid ABCD is tangent at any point on circular arc DE whose center is O. Find the length of BC so that the area of ABCD is maximum.