设f'(x)=3,则lim h→∞ (f(x+2h)-f(x))/h=?

设f'(x) = 3^(1/2) ,求 lim(h→0) [f(x+mh) - f(x - nh)] / h ,(m , 设f(x)在x=2处可导,f'(2)=2,则lim h→0 [f(2-3h)-f(2)]/h=? 设f(x)在x=2处可导,且f'(2)=1,则lim h→0 [ f(2+h)-f(2-h)]/h等于多少, 设函数f(x)在x=x0处可导,则lim(h>0)[f(x0)-f(x0-2h)]/h 设f(x)为可导函数,且lim(h→0) f(3)-f(3+h)/2h=5,则f'(3)等于? 设f(x)在x=0处可导,则lim(h趋于0)(f(3h)-f(-h))/2h=? 设f(x)具有二阶导数f''(x),证明f''(x)=lim(f(x+h)-2f(x)+f(x-h))/h^2 设函数f(x)在x=1处可导,且f'(1)=2,则[lim(h→0)f(1-h)-f(1)]/h等于 设f(X)在x=x0处具有二阶导数f''(x0),试证:lim(h→0)(f(x0+h)-2f(x0)+f(x0-h)) f(x)在x=a处可导, lim(h→0) [f(a+h)-f(a-2h)]/h= 若f(x)有二阶导数,证明f''(x)=lim(h→0)f(x+h)-2f(x)+f(x-h)/h^2. 设函数f(x)在点x0处可导,且f'(x0)=2,则lim(h→0)[f(x0-h/2)-f(x0)]/h等于多少