1. ก ก
( 31102)
!"# $% กก& $#
'& (
") * +#
,& -ก .
(# */0 +' *
& ก# % '!ก 1ก. *2 * ก. % 36
1

2. ก'! n %"# & + #
ก % $% กก& $# *!" $%,ก& $# 45 & + ก6
* 7'& 8 ( " + * !"# ก'! n %"# & + # a
(91!# % ' + -$ก. n a ) $6*:' * #
:' * 0; n 45 & + <*:+ก'!* กก+/ 1
a $6 b 45 & + #
b 45 ก'! n %"# a ก< /" *!" (b) n = a

3. ก n a +/ / ;$ก%"# ก'! n %"# a ; "
ก ='! n %"# a
0 ก '!+84*%" )4 ก! +ก: / ;$ก%"# ก'! n%"# a; " n a #
n
1. 7 a = 0 , a = 0
2. 7 a > 0 ,
n a 45 & + #
na
3. 7 a < 0 $6 n 45 & + ! 6 45 & + $:
n 45 & + / n a 8*/0,/ & + #
;* ; ) 7 n = 2 6% ' 2a + a

4. +" / #'! 1
2 45 ก'! 2 %"# 4 6 (2)2 = 4
3 45 ก'! 3 %"# 27 6 (3)3 = 27
- 5 45 ก'! 3 %"# - 125 6 (- 5)3 = -125
2 45 ก'! 5 %"# 32 6 (2)5 = 32
+" / #'! 2
/ ;$ก%"# ก'! 4 %"# 81 " 3
/ ;$ก%"# ก'! 3 %"# 216 " 6
/ ;$ก%"# ก'! 5 %"# 27 " 5 27
/ ;$ก%"# ก'! 7 %"# -128 " -2

5. *: %"# ก'! n
1. ( a)
n
n
= a *!"
na
45 & + #
( )
5
+" / # 2
3 = 3 5 − 4  = − 4
 
 
2. n a n = a *!" a ≥ 0
n n
a = a *!" a < 0 $6 n 45 & + !:+ก
n n
a = a *!" a<0 $6 n 45 & + /:+ก
+" / # 32 = 3 4 (−3)4 = −3 = 3
5
−8 5
= −8

6. *: %"# ก'! n( /")
3. n ab = n a •n b
32 = 16 • 2 = 16 • 2 = 4 2
+" / # 3 250 = 3 (−125)(2) = 3 (−125) • 3 2 = − 53 2
n a n a
4. = , b ≠ 0
n b n b
35 35
+" / # 3 5 = =
27 3 27 3
4 16 4 4
4 16 = =
2
=
2
81 4 81 4 4 3
3

7. +" / #
+" / # #% & + /"84 0;" /0 4" / ##/
500
+2'&
500 = 100 × 5 = 100 ⋅ 5 = 10 5
3 810
+2'& 3
810 = 3
27 × 30 = 3
27 3 30 = 33 30
125
+2'& 125 = 25 × 5 = 25 ⋅ 5 = 5 5