Question

(x+1)+(x+2)....(x+9)=0

 

Answer 1

(x + 1) + (x + 2) + ....+ (x + 9) = 0

=> (x + x + ....+ x) + (1 + 2 + ...+ 9) = 0

=> 9x + 45 = 0

=> 9x = -45

=> x = -5

Answer 2

<=> 9x+1+2+...+9=0

<=> 9x=-(1+2+..+9)

Xét 1+2+..+9

SSH:9

Tổng: 45

=> -(1+2+..+9)=-45

=>9x=-45=>x=-5