2. กก
กก
F a n ก
an = a ⋅a ⋅ . . .⋅a
n
ก a F กก
ก n F ก
3
F 2 = 2⋅2⋅2 = 8
3. F a,b m,n
1. a m a n = a m +n F 2 2 ⋅ 2 4 = 2 2+ 4 = 26
2. (a m ) n = a mn F (52 ) 6 = 52⋅6 = 512
3. (ab ) m = a m b m F ( 2 ⋅ 3) 2 = 2 2 ⋅ 3 2 = 36
m 2
4. a am F 3 32 9
= , b ≠0 = 2 =
b bm 4 4 16
4. F n กa
a ≠ 0 F a −n
=
1
an
F
1 1
−2
= = a2 , a ≠ 0
a 1
a2
5. F a a ≠0 F a0 = 1
am
= a m −n
an
F 28
= a 8−3 = a 5
23
3−1 6
= = 2
6 −1 3
6. กก nn
กF F x ก aก F x2 = a
x a F ก
ก 1 a ก
ก a ก F a
ก a F − a
15. x2 −y2 + x
F F x2 + y2 −y
x2 + y2 + y x − x 2 −y 2
x2 −y2 + x x2 + y2 −y
2 2
÷
x + y + y x − x 2 −y 2
= x2 −y2 + x
×
x − x2 −y2
2 2
x + y + y x 2 +y 2 − y
= x + x2 −y2
× x − x2 −y2
2 2
x + y + y x 2 +y 2 − y
x 2 − (x 2 − y 2 ) y2
= =
x 2 +y 2 −y 2 x2