直接用基本公式(x^m)'=mx^(m-1)和(x)'=1y'=2x+1按照导数定义:y'=lim[h→0] {[(x+h)²+(x+h)]-(x²+x)}/h=lim[h→0] (x²+2xh+h²+x+h-x²-x)/h=lim[h→0] (2xh+h²+h)/h=lim[h→0] (2x+h+1)...