Question

Suma lui Gauss
4+5+6+.....+98=
AJUTOR !!!|
Repede!
Va rog!

Answer 1

4 + 5 + 6 + ... + 98 =
n = ( 98 - 4 ) : ( 5 - 4 ) + 1
n = 94 : 1 + 1
n = 94 + 1
n = 95
S = [( 98 + 4 ) x 95 ] : 2
S = ( 102 x 95) : 2
S = 9690 : 2 
S = 4845.

Answer 2

$4+5+6+.....+98 = 1+2+3+4+5+6+...+98 - (1+2+3) = \\ \\ = \frac{98\cdot99}{2}-6 = 49\cdot 99 - 6 = 4851-6 = 4845$