(.a-b)2 = a--2ab + b2 (a+b)2 = a2 + 2ab + b2 a2 - b2 = (a-b)(a+b)
(a-b)3 = a3 - 3a2b + 3ab2 - b3 (a+b)3 = a3 + 3a2b + lab2 + b3 a3 - b3 = (a - b)(a2 + ab + b2) a3 + b3 = (a + b)(a2 - ab + b2)
(j2ń-j2^I)(j2ń+JbPi)
a) lim ^ĘEL = lim
7 nr1
n—
lim -2n~2^\_ lim
n—>y: (nr\)(j2n— J2n— 1 ) n—>y:
e) lim -Hm ^n'3~n~~n'>(-\l(-r,:'~n2'>1 +2nljn>-n2 +«2)
n—> cc
n—> cc
2( jj|f(w3-w2)2+2w^/w3-w2+w2 )
lim
nr—nr—nr
= lim
-W
w—*-cc 2(jjf(wJ-w2)2 +2w^/w3-w2 -1-rc2) rc—*-cc 2(^(rc:‘-rc2)2 +2w^/w3-w2+w2)
lim "”2 - "i - - 1
n—•■oc 2(3/(«3-«2)2+2w2^r4+„^
2-3
i) lim (V^T - ń) =lim =
lim ""Iz"2 -lim
(Jn~-\rn) w—*-cc (Jn--\rn)
= o
n—
n—