先化简(2x-1)²-(3x+1)(3x-1)+20x³(x-1)÷(-2x)²

问题描述:

先化简(2x-1)²-(3x+1)(3x-1)+20x³(x-1)÷(-2x)²

=4x^2+4x-(9x^2-1)+5x^2(x-1)
=2-x

=4x^2+1-4x-9x^2+1+[20x^3(x-1)/4x^2]
=4x^2-9x^2-4x+2+5x^2-5x
=2-5x-4x
=2-9x

(2x-1)²-(3x+1)(3x-1)+20x³(x-1)÷(-2x)²=(2x-1)²-(9x²-1)+5x(x-1)
=4x²-4x+1-9x²+1+5x²-5x
=-9x+1