Question

fisa se rezolve ecuatia 2+6+10+...+2x=338​

Answer 1

Răspuns:

2+6+10+...+2x=338

2(1+3+5+....x)=338║:2

1+3+5+....+x=169

Aplici formula

1+3+5+...+(2n-1)=n²unde

2n-1=x

n²=169

n=√169=13

x=2n-1=2*13-1=26-1=25

Deci

x=25

Explicație pas cu pas: