设f为定义在(a,+∞)上的函数,在每一有限区间(a,b)上有界,且limx→+∞[f(x+1)-f(x)]=A,证明limx→+∞f(x)x=A.
lim |
x→+∞ |
f(x+n)?f(x) |
n |
f(y)?f(y?[y?x]) |
[y?x] |
f(y) |
y |
[y?x] |
y |
f(y)?f(y?[y?x]) |
[y?x] |
f(y?[y?x]) |
y |
lim |
y→+∞ |
f(y) |
y |
lim |
y→+∞ |
[y?x] |
y |
f(y)?f(y?[y?x]) |
[y?x] |
lim |
y→+∞ |
f(y?[y?x]) |
y |
lim |
y→+∞ |
f(y?[y?x]) |
y |
lim |
x→+∞ |
[y?x] |
y |
f(y)?f(y?[y?x]) |
[y?x] |
lim |
y→+∞ |
f(y) |
y |
lim |
x→+∞ |
f(x) |
x |