Question

Calculati: 1+2+3+4...+2000+2001
Va rog sa ma ajutati.

Answer 1

1+2+3+4+2000+2001=
3+3+4+2000+2001=
6+4+2000+2001=
10+2000+2001=
2010+2001=
4011

Answer 2

1+2+3+4+...+2000+2001
n=(U-P):r+1
n=(2001-1):1+1
n=2000:1+1
n=2001
S=1+....+2001
S=2001+...+1
⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻
2S=2002 x 2001 (numarul de numere adica n)
S=2002x2001:2
S=1001x2001
S=20003001
1+2+3+4+...+2000+2001=2003001

P.s:(U)=Ultimult nr.
      (P)=Primul nr.
      (r)=ratie
      (n)=nr.de numere
      (S)=Suma
Sper ca te-am ajutat!Succes!!