Question

Imi puteti explica si mie un ex ? A = 100 + 2 x ( 1 + 2 + 3 + ..... + 99 ) este patrat perfect

Answer 1

$A=100+2(1+2+3+...+99)=100+\frac{2*99*100}{2}=100+99*100=100*100=100^2 -este \ p.p$