x^2(x-1)^2-4x(x-1)-12
x*x+2x+x*x+10x+x*x+25+2x+x*x+1+1+16+x*x+4x*x+9-12x+16x*x+4-1
x+2/x+1-x+3/x+2-x+4/x+3+x+5/x+4
x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x
|X-1|+|X-2|+|X-3|+|X-4|+|X-5|+|X-6|+|X-7|+|X-8|+|X-9|+|X-10|
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
x(2-1/x)+x/(x^2-2x)÷(3-x)/(x^2-4)
解方程(x/x(x+2))+(x/(x+2)(x+4))+.+x/(x+8)(x+10)=1
x^4+x^3+x^2+x+1=0,x^2006+x^2005+x^2004+x^2003+x^2002
因式分解x^4-x^-2-x+1
|x^2-3x-4|>x+1
2x-1>4x;x+51
(x+1-1/1-x)÷(x-x²/x-1) (x-4/x-x-6+ x+2/x-3)÷x+1/x-3