" "
" "
n2- n-1
"
limn" n2+ n+1- "
n+1- n
n(n+2)
limn" n2-3
n2+2
"
2
x8x cosh x2
f(x) = x arctan x
f(x) = x-x (0, +")

1 1 1
limn" n + + · · · +
1+n2 2+n2 n+n2
2
(n-1)
n2+4
limn" n2-1

x
limx" tanh sinh(5x2 - 1)
2
a, b, c, d, e, f f R
Å„Å‚
0 x < -1
ôÅ‚
ôÅ‚
òÅ‚
x3 + ax2 + bx + c - 1 d" x < 0
f(x) =
ôÅ‚ -x3 + dx2 + ex + f 0 d" x < 1
ôÅ‚
ół
0 1 d" x
l