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  1.  
  2.                 Review of Algebraic Expressions and Exponents
  3.                 flflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflflfl
  4.  
  5. You MUST have all the following information at your fingertips at all times.
  6.  
  7.             You have NO CHANCE of passing calculus without it.
  8.   
  9.             
  10.                     (a + b) (c + d)   =   ac + ad + bc + bd
  11.  
  12.                                   2        2          2
  13.                            (a + b)    =   a  + 2ab + b 
  14.  
  15.                                            2
  16.                      (x - a) (x - b)  =   x  - (a + b)x + ab
  17.  
  18.                                            2    2
  19.                      (a - b) (a + b)  =   a  - b 
  20.  
  21.                         2         2        3    3
  22.               (a - b) (a  + ab + b )  =   a  - b 
  23.  
  24.  
  25. If a and b are positive integers:
  26.  
  27.                                  a b      a+b
  28.                                 x x   =  x 
  29.  
  30.  
  31.                              a
  32.                             x        a-b       1
  33.                            ƒƒƒƒ  =  x    =  ƒƒƒƒƒƒ
  34.                              b                b-a
  35.                             x                x
  36.  
  37.                                a  b      ab
  38.                              (x )    =  x
  39.  
  40.                                   a      a a
  41.                               (xy)   =  x y
  42.  
  43.                                   a      a    a
  44.                              (x/y)   =  x  / y
  45.  
  46.  
  47.  
  48. ⁄ƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒø
  49. ≥ Common Mistakes ≥
  50. ¿ƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒŸ
  51.  
  52. WRONG    - (x - y)  =  -x - y           RIGHT    - (x - y)  =  -x + y
  53.  
  54. WRONG     2(x + y)  =  2x + y           RIGHT     2(x + y)  =  2x + 2y
  55.  
  56.                  2      2         2                      2      2          2
  57. WRONG     (x + y)   =  x  + xy + y      RIGHT     (x + y)   =  x  + 2xy + y
  58.  
  59.                  2                                       2      2          2
  60. WRONG     (x - y)   =  (x - y)(x + y)   RIGHT     (x - y)   =  x  - 2xy + y
  61.  
  62.  
  63.               2 3       5                             2 3       6
  64. WRONG       (x )    =  x                RIGHT       (x )    =  x
  65.  
  66.              2  3       6                            2  3       5
  67. WRONG       x  x    =  x                RIGHT       x  x    =  x
  68.  
  69.  
  70. This is the end of the help file.  Press the ESC key to return to the quiz
  71. question you were doing.
  72.