Răspunsuri

2014-11-19T11:23:11+02:00
Suma =99*100/2=4950
a=2*4950-99=9900-99=9801
a=99^2
rezulta p.p

2014-11-19T13:08:25+02:00
A=2x(1+2+3+4...+99)-99=
=2x99x10:2-99=
=99x100-99=
=99(100-1)=
=99x99=
=99²