... i2···i 99 · i 10 0= 1. 2+T`ım sˆo´nguyˆen n nˆe´u:a) (1 + i)n= (1 i)n;b) 1+ i√2n+ 1 − i√2n=0.Gia’i. 1 +Ta c´o i0 =1, i 1 = i, i2= 1, i3= −i, i4 =1, i5= ... = −3. (1. 4)T`u. (1. 4) ta c´o b = −32a.Thˆe´v`ao (1. 3) ta thu du.o..c4u2− 16 u − 9= 0,u= a2⇐⇒u 1 =8+√ 10 04=8 +10 4= 18 4= 9 2,u2=8 −√ 10 04=8 − 10 4= − 1 2·V`ı ... th´u.c 89 3.3 Ha.ng cu’a ma trˆa.n 10 9 3.3 .1 D-i.nhngh˜ıa 10 9 3.3.2 Phu.o.ng ph´ap t`ım ha.ng cu’a ma trˆa.n 10 9 3.4 Ma trˆa.n nghi.ch da’o 11 83.4 .1 D-i.nhngh˜ıa 11 83.4.2...