M4maths Previous Puzzles

07 Jan 2010 Find the minimum value?

Minimum value of sum of a number and its square is ?
(Only real numbers are allowed)

OPtion

1) -1/4
2) -1/2
3) 0
4) 1/2
5) 1/4
6) 6
7) 2
8) -1/3
9) -1
10) 1

Solution

x + x2
= x + x2 +1/4 -1/4
= (x+1/2)2 -1/4
On taking x = -1/2, we get the minimum value of x + x2 as -1/4

Correct Option: 1 Best Solution (5)