(3x+2)(3x-2)-5x(x-1)-(2x-1)²=(3x)²-2²-5x²+5x-(4x²-4x+1)=9x²-4-5x²+5x-4x²+4x-1=9x-5
=9X^2一4一5x^2十5一4x^2十4x一1二4x
