9.
[2+x ]=-[x]²+4
      [x]²+ [2+x ]=4
     Puntos críticos
      X=0
      2+x=0
     X=-2
     [ a ] + [ b ] puntos críticos donde se iguala a cero
                                                     2            1
                8                   3
       -                                   -2                0
                     X < -2             -2 < x < 0       x > 0ç
           ❶X=1                                                   ❷ x=1
      [ x ] ²+[ 2+x ] = 4                                             - [ x ]²+( 2 + x ] = 4
           x² + x + 2 – 4 = 0                                         - x² + 2 + x = 4
            x² + x – 2 = 0                                                            0 = x² - x – 2 + 4
            x            +2 2x                                                        0 = x² - x + 2
                                        −x
            x                  -1                                               formula general
                                         x
            (x+2) (x-1) = 0                                             a= 1
            X = -2 ^ x = 1                                              b= -1
                                                                        C= 2
                                                                                      −1 .−1 ± √ 12−4 .1(2)
            ❸ x = -3                                                             x=
                                                                                                   2 .1
                                                                                       −1.−1 ± √ 1−4.1 .2
                    - [ x ]²+( 2 + x ] = 4                                       x=
                                                                                                   21
                                                                                       −1.−1 ± √1−8
                     - x² + 2 - x = 4                                             x=
                                                                                                2.1
                                                                                          −1.−1 ± √ 7
                              0 = x² + x + 4 + 2                                     x=
                                                                                                2 .1
                                                                                           −1.−1 ± √ 7
                              0 = x² + x + 6                                          x=
                                                                                                   2
                                                                                            1± √ 7
                     formula general                                                   x=
                                                                                               2
                     a= 1                                                La factorización en primos de −7 es i√ 7
                      b= 3                                                              √−1 .7=i √ 7
                      c= 6                                                          factores primos
               −1 ± √ 1 −4 .1(6)    2
            x=                                                                                 i √ 7=i √ 7
                      2 .1
               −1 ± √ 1−24                                                                     x=
                                                                                                   1± i √ 7
            x=
                   2 .1                                                                               2
               −1 ± √−23                                                                       x 1=
                                                                                                    1+i √ 7
            x=
                   2                                                                                   2
                                                         −1i √ 7
Factor primo de -23 es   i √ 23                   x 2=
                                                           2
√ ❑−23=√ −1.23
Factores primos
i √ 23=i √ 23
     −1 ±i √ 23
x=
         2
      −1+i √ 23
x 1=
          2
      −1−i √23
x10.
  2= [ x – 3 ] [ x + 5 ] + x = 2
          2
       [x–3][x+5]=2–x
         [ (x – 3) (x + 5) ] 2 – x
         [ 6x² + 5x – 3x – 15 ] = 2 – x
         [ x² + 2x – 15 ] = 2 – x
[a ]=a                               ^     [ a ] = -a
x² + 2x – 15 = 2 – x                        x² + 2x – 15 = - (2 – x)
x² + 3x – 17 = 0                            x² + 2x – 15 = - 2 + x
formula general                           x² + x – 13 = 0
a= 1                                      formula general
b= 3                                      a= 1
c= - 17                                   b= 1
    −3 ± √ 32−4 .1(−17)
 x=                                        c= -13
             2 .1
     −3 ± √ 9+68                               −1 ± √ 12−4 .1(−13)
x¿                                        x=
         2.1                                            2 .1
     −3 ± √ 77                                 −1 ± √ 1+52
x¿                                        x=
       2 .1                                        2.1
     −3 ± √ 77                                 −1 ± √ 53
x¿                                        x=
        2                                        2 .1
                                               −1 √53
separa                                    x=
                                                 2
     −3+ √ 77
x¿                                        separa
       2
     −3−√ 77        −1+ √ 53
x¿             x=
       2              2
x1¿ √
        77−3        −1−√ 53
               x=
         2            2
x2= √                 √53−1
   − 77−3                             − √53−1
               x 1=            x 2=
          2             2                 2