Question

[Thuy Tran Thi]

(x+1/2)+(x+1/4)+(x+1/8)+(x+1/16)= 31/16 
ai trả lời nhanh mình like

Answer 1

[Nguyễn Thị Thương Hoài]

(\(x+\dfrac{1}{2}\)) + (\(x+\dfrac{1}{4}\)) + (\(x+\dfrac{1}{8}\)) + (\(x+\dfrac{1}{16}\)) = \(\dfrac{31}{16}\)

\(x+\dfrac{1}{2}+x+\dfrac{1}{4}\) + \(x+\dfrac{1}{8}\) + \(x\) + \(\dfrac{1}{16}\) = \(\dfrac{31}{16}\)

(\(x+x+x+x\)) + (\(\dfrac{1}{2}\) + \(\dfrac{1}{4}\) + \(\dfrac{1}{8}\) + \(\dfrac{1}{16}\)) = \(\dfrac{31}{16}\)

4\(x\) + (\(\dfrac{8}{16}\) + \(\dfrac{4}{16}\) + \(\dfrac{2}{16}\) + \(\dfrac{1}{16}\)) = \(\dfrac{31}{16}\)

4\(x\) + \(\dfrac{15}{16}\) = \(\dfrac{31}{16}\) 

4\(x\)           = \(\dfrac{31}{16}\) - \(\dfrac{15}{16}\)

  4\(x\)         = 1

     \(x=\dfrac{1}{4}\)

Answer 2

[Ninh Duy Phong]

(x + 1/2) + (x + 1/4) + (x + 1/8) + (x + 1/16) = 31/16

x \(\times\) 4 + (1/2 + 1/4 + 1/8 + 1/16)                   = 31/16

Đặt 1/2 + 1/4 + 1/8 + 1/16 là A

A = 1/2 + 1/4 + 1/8 + 1/16

2xA = 1 + 1/2 + 1/4 + 1/8

2xA-A = (1 + 1/2 + 1/4 + 1/8)-(1/2 + 1/4 + 1/8 + 1/16)

A = 1 - 1/16

A = 15/16

Thay ...

x \(\times\) 4 + 15/16 = 31/16

x \(\times\) 4              = 1

x                     = 0,25

Vậy x = 0,25