中三maths 希望能列式=]

a) 5^x=125
5^x=5^3
x=3

b)3^2y-1=27
3^2y-1=3^3
2y-1=3
2y=4
y=2

c)2^6-z=4^6+z
2^6-z=2^12+2z
6-z=12+2z
-6=3z
z=-2


2010-09-12 10:31:26 補充：
(3a^-2b^3)^-2*(4ab-1)^2/(a^2b^3/(2a)^-3
=(3)^-2*a^4*b^-6*(4)^2*a^2*b^-2/(8b^3/a)
=a^4/9b^6*16a^2/b^2*a/8b^3
=16a^15/9b^11

2010-09-12 10:45:39 補充：
(3a^-2b^3)^-2*(4ab-1)^2/(a^2b^3/(2a)^-3
=3^-2*a^4*b^-6*16*a^2b*-1/(a^2b^3/2^-3*a^-3)
=(16a^6/9b^7)/(a^2b^3/2^-3*a^-3)
=(16a^6/9b^7)*(2^-3*a^-3/a^2b^3)
=2a/9b^11

圖片參考：http://img13.imageshack.us/img13/3873/screenhunter01sep121036.gif


http://img13.imageshack.us/img13/3873/screenhunter01sep121036.gif

(a) 5x=53
x=3


(b) 32y-1= 33
2y-1=3
2y=4
y=2


(c) 26-z = 22(6+z)
6-z=2(6+z)
6-z=12+2z
3z=18
z=6