Question

hallar el valor de:E=1×2+2×4+3×6+...+15×30​

Answer 1

Respuesta:

E=2480

Explicación paso a paso:

E=1×2+2×4+3×6+...+15×30​

E=2+8+18+....+450

E=2(1+4+9+.....+225)

E=2($1^{2}$+$2^{2}$+$3^{2}$+…..+$15^{2}$)

E=2x15(15+1)(2x15+1)/6

E=30X16X31/6

E=14880/6

E=2480

Formula utilizada:

P=$1^{2}$+$2^{2}$+$3^{2}$+…..+$n^{2}$

P=n(n+1)(2n+1)/6