Question

Aflați-l pe x din ecuatia :
$\frac{x + 1}{2} + \frac{x +2}{3} + \frac{x + 3}{4} + ... + \frac{x + 9}{10}- 9 = 0$
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Answer 1

Răspuns:

(x+1)/2+(x+2)/3+(x+3)/4+...+(x+9)/10-9=0

suma are 9 termeni

(x+1)/2-1+(x+2)/3-1+(x+3)/4-1+...+(x+9)/10-1=0

(x-1)/2)+(x-1)/3+(x-1)/4+...+(x-1)/10=0=

(x-1)(1/2+1/3+1/4+...+1/10)=0=>

x-1=0=>

x=1

Explicație pas cu pas: