1.计算:x-y分之x+y + y-3分之2x 2.计算:x+3分之x²-x-2 除以 (2-x) + x+3分之x+1
问题描述:
1.计算:x-y分之x+y + y-3分之2x 2.计算:x+3分之x²-x-2 除以 (2-x) + x+3分之x+1
答
1.计算:x-y分之x+y + y-3分之2x=(x+y)/(x-y)+2x/(y-3)=((x+y)(y-3)+2x(x-y))/(x-y)(y-3)=(xy-3x+y^2-3y+2x^2-2xy)/(x-y)(y-3)=(-3x+y^2-3y+2x^2-xy)/(x-y)(y-3)=(-3x-3y+y^2-xy+2x^2)/(x-y)(y-3)2.计算:x+3分之x...