Respostas

2014-03-24T20:50:44-03:00
1) resolva :(x+1)² +(x-1)² - 2(x²-1)= 
x² + 2x +1 + x² - 2x +1 -2x² +2
4
1 4 1
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2014-03-24T20:58:07-03:00
(x+1)²+(x-1)²-2(x²-1)
(x²+2.x.1-1²)+(x²-2.x.-1-1²) -2x²+2= 
x²+2x+1+x²+2x+1-2x²+2=
x²+x²-2x²+2x+2x+1+1+2=
+4x+4=0
4x=4
x= 4÷ 4
x= 1
3 3 3