Question

Aratati ca urmatoarele numere sunt patrate perfecte

a) 2+2+2^2+2^3+2^4+2^5
b) 1+3+5+7+9
c) 8+2×(1+2+3+4+5+6+7)
d) 101+(2+4+6+...+200)

Answer 1

a) = 4+4+8+16+32=64=8²

b) = 25 = 5²

c)= 8 + 2 * 28 = 8+56 = 64 = 8²

d) 101 + 2*(1+2+...+100) = 101+2*((100*101) :2) = 101+10 100= 10 201 = 101²