求下列各式的值:x(x+2y)-(x+1)^2+2X,其中x=1/25,y=-25

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求下列各式的值:x(x+2y)-(x+1)^2+2X,其中x=1/25,y=-25
求下列各式的值:x(x+2y)-(x+1)^2+2X,其中x=1/25,y=-25

求下列各式的值:x(x+2y)-(x+1)^2+2X,其中x=1/25,y=-25
x(x+2y)-(x+1)^2+2x
=x^2+2xy-x^2-2x-1+2x
=2xy-1
=2*(1/25)*(-25)-1
=-2-1
=-3

请问其中那个(x+1)与2之间的符号什么意思

x(x+2y)-(x+1)^2+2x
=x^2 + 2xy - (x^2 + 2x +1) + 2x
=x^2 + 2xy - x^2 - 2x -1 + 2x
=2xy -1
=2*1/25*(-25) - 1
=-3

x(x+2y)-(x+1)^2+2X
=x^2+2xy-(x+1)(x+1)+2x
=x^2+2xy-x^2-2x-1+2x
=2xy-1
=2*1/25*(-25)-1
=-3

x(x+2y)-(x+1)^2+2x
=x^2+2xy-x^2-2x-1+2x
=2xy-1
=2*(1/25)*(-25)-1
=-2-1
=-3