решите неравенство: 1) 7<2-5x<13 2) 9<3-4x<15 3) x<или=3 - 1/x-1

Question

решите неравенство:

1) 7<2-5x<13</p>

2) 9<3-4x<15</p>

3) x<или=3 - 1/x-1</p>

Answer 1

1) 7<2-5x<13      2) 9<3-4x<15        3) x<или=3 - 1/x-1</p>

  7-2+5х<13             9-3+4x<15          x=3-1/x-1</p>

  5+5x<13                 6+4x<15              x=3x-1-x</p>

  5x<13-5                  4x<15-6               x=2x-1</p>

  5x<8                        4x<9                    x-2x=-1</p>

  x<8-5                       x<9-4                  -x=-1</p>

  x<3                          x<5                       x=1</p>