Respostas

2014-04-11T12:17:45-03:00
2014-04-11T12:24:49-03:00
Calcule o valor das expressões númericas:

a) (-2)² + 2-¹ =

   (-2)² +  2-¹ = 4 + 1/2¹

                acha mmc 

                       8 + 1
                       ------ = 9/2  =  ou 4,5
                          2

 b) (-2)4.4-² - (-2)³ =
     (-2)4.1   -(-2)³ =
    - 8       - (-8)
---------              =
     4²

 
- 8     + 8                                   - 8 + 128           120
------         =    achar mmc          -----------  =        ----   = 8
 16                                                 16                   16


c) (2 + 2 -¹) / 4 -¹


    (2 + 1)                         4 + 1                    5 
           ---                          ------                   ----
           2¹                              2                      2
______________= ____________  =     _______ =                                     
           1                              1                       1
          ---                            ----                     ---                                               
           4¹                             4                        4  

atenção divisão em cima de divisão COPIA O 1º E  inverte o segundo multiplicando

 Então
5      4           20
--  x  -- =       -----  = 10
2      1             2