1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
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|
1/6x+1/12x+1/7x+5+1/2x+4=x
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
提取公因式:已知x*x-5x+1=0 求x*x*x-4x*x-4x-1
x-(1/5+1/5)x-39=39 x-1/4x-2/5x=112 x-1/6x-1/3x-12=20
解方程1/(x+x﹚+1/(x+3x+2﹚+1/(x+5x+6﹚+1/(x+7x+12﹚=4/21得
求1/2x^2-1/4x+0.2x^3+0.25x-0.5x^2-1/5x^3+0.5x-1 其中x=12/13
x-1=3x+3 x-3=12-4x 6x-14=5x-10 x+1=2-4x
x²(x-1) - 4x(x-1) - 12