x^2-x-2012=0
x²-x=2012
(3x+2)(3x-2)-5x(x+1)-(x-1)^2 5x(x-1)换成5x(x+1)
=9x²-4-5x²-5x-x²+2x-1
=3x²-3x-1
=3(x²-x)-1
=6036-1
=6035