4x/(x²+x+3) + 5x/(x²-5x+3)= - 3/2
4x²-{-3x²-[5x-x²-(2x²-x)]+4x},其中x=½
(1) x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8
x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x
4x/(x²+x+3) + 5x/(x²-5x+3)= - 3/2
x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?
f(x)=x²+3x|x-2|
(x+2/x+1)-(x+4/x+3)-(x+3/x+2)+(x+5/x+4)
计算(x*x+4x+5)/(x+2)-(x*x+6x+10)/(x+3)+1
解方程(x-2)X(x的平方-6x-9)=x(x-5)X(x-3)
(先化简后求值)(3x/x+2-x/x-2)+2x/x^2-4,x=4-根号5,
2x+3x+4x+5x+x+6x+7x=100
3x²-【5x²+(3x²-2x)-(2x²-4x)】 化简