Question

calcula: 1+8+27+64+....+9261

Answer 1

Recuerda:

${1}^{3} + {2}^{3} + {3}^{3} + ... + {n}^{3} = {( \frac{n(n + 1)}{2} )}^{2}$

...

$= {1}^{3} + {2}^{3} + {3}^{3} + {4}^{3} + ... + {21}^{3}$

$= {( \frac{21(22)}{2}) }^{2}$

$= {231}^{2}$

$= 53361$