Respuesta :

Answer:

[tex]3 < x < 5[/tex]

Step-by-step explanation:

Given inequality:

[tex]|2x - 8| < 2[/tex]

[tex]\textsf{Apply absolute rule}: \quad \textsf{If }|u| < a\:\textsf{ when } \: a > 0,\: \textsf{then }-a < u < a[/tex]

[tex]\implies u=2x-8\: \textsf{ and }\:a=2[/tex]

[tex]\implies -2 < 2x-8 < 2[/tex]

Therefore:

[tex]\implies -2 < 2x-8[/tex]

[tex]\implies 6 < 2x[/tex]

[tex]\implies 3 < x[/tex]

And:

[tex]\implies 2x-8 < 2[/tex]

[tex]\implies 2x < 10[/tex]

[tex]\implies x < 5[/tex]

Merge the overlapping intervals:  [tex]3 < x < 5[/tex]

Proof

Graph:  [tex]y=|2x-8|[/tex]

Add a line at  [tex]y=2[/tex]

The interval that satisfies  [tex]|2x - 8| < 2[/tex]  is the area under the points of intersection (shaded area on the attached graph).

The values of x when [tex]y=|2x-8|[/tex] is less than 2 is more than x = 3 and less than x = 5.

Ver imagen semsee45
  • |2x-8|<2

So

Case-1

  • 2x-8<2
  • 2x<2+8
  • 2x<10
  • x<5

Case-2

  • 2x-8>-2
  • 2x>6
  • x>3

So solution is

  • 3<x<5