Question

A triangle is inscribed in a circle of radius 1. The maximum value of sum of the squares of the sides is-

• A. 9
• B. 6
• C. 3
• D. 8

Answer 1

Answer: (A)

9

Answer 2

Let the position vectors of the vertices of the triangle be , $\overrightarrow { \mathrm { b } }$ and $\overrightarrow { \mathrm { c } }$ respectively.

Ž sum of squares of the sides

=|– $\overrightarrow { \mathrm { b } }$ |² + | $\overrightarrow { \mathrm { b } }$ – $\overrightarrow { \mathrm { c } }$ |² + | $\overrightarrow { \mathrm { c } }$ – |² £ 9