1.2x^2+x >0
解方程 1.2x+8.8x=78 2x+9x-1.1=0 6.9x-3.8x=46.5 7.8x+2.2x=43.6
f(x)={x^2+x(x≤0),-x^2+x(x>0)
f(x)分段函数-x^2+x(x≥0),x^2+x(x
x^4+x^3+x^2+x+1=0,x^2006+x^2005+x^2004+x^2003+x^2002
x^2-2x>0 x>2 x
(x-2)(x-3)/(x+5)(x-7)>0
解方程 x*x*x + 2*x -19 =0
求极限lim(x->0)(x+e^x)^2/x
(x+2)(x-3)(x-6)(x-1)=0
lim(x->0)((2-x)/(3-x))^1/x
1.2-5x+x*x2.2x*x-5x+13.x*x-3/2*x-24.-x*x-4x+3
已知1+x+x^2+x^3=0,求x+x^2+x^3+x^4+x^5+x^6+x^7+x^8的值