Răspuns:
[tex]s \: = \frac{x \times x + 1}{2} [/tex]
[tex]a = \frac{399 \times 399 + 1}{2} = \frac{159.600}{2} = 79.800[/tex]
[tex]b = ( \frac{560 \times 560 + 1}{2} ) \div 4 =( \frac{314.160}{2} ) \div 4 = 157.080 \div 4 = 39.270[/tex]
79.800 > 39.270 => A > B
