Respostas

2014-08-16T18:54:36-03:00
A) D = -7

b) 2.7 - 3.9 = 14 - 27 = -13

c) 1.2 - 2.(-1) = 2 + 2 = 4

d) (-2).(-3) - 0.4 = 6 - 0 = 6

e) (1/2).4 - 3.(1/3) = (4/2) - (3/3) = 2 - 1 = 1

f) a.(-a) - (-a).(-a) = -a - a = -2a