Odpowiedzi

2009-12-01T15:33:12+01:00
1-4(x+2)²=(1-2)(1+2x)=
1-4x^2-16= 1+2x+2-4x
-2x+4x-4x^2=-1+16+1+2
2x-4x^2=18/:4
2x- x^2=12 /:2
x-x^2=6