(3^2+4y)-(3x^2+5y-3)-(-2x^2-5y-3)-(2x^2-5y+5)其中X=-3 Y=-4

问题描述:

(3^2+4y)-(3x^2+5y-3)-(-2x^2-5y-3)-(2x^2-5y+5)其中X=-3 Y=-4

原式=3x^2+4y-3x^2-5y+3+2x^2+5y+3-2x^2+5y-5
=9y+1
=9*(-4)+1
=-35

(3x^2+4y)-(3x^2+5y-3)-(-2x^2-5y-3)-(2x^2-5y+5)
=3x²+4y-3x²-5y+3+2x²+5y+3-2x²+5y-5
=9y+1
当x=-3,y=-4时
原式=-36+1=-35