急 ! Logarithmic Function 9q3

as follows:

圖片參考：http://imgcld.yimg.com/8/n/HA04937267/o/701203300063913873385212.jpg



圖片參考：http://imgcld.yimg.com/8/n/HA04937267/o/701203300063913873385223.jpg


2012-03-30 23:21:48 補充：
you can get a clearer image if you save the above pictures in your computer then open it.

2012-03-31 01:24:53 補充：
回下面
7a 你錯左-.-...自己計多次:)
10a 2log3 = log3^2 = log 9
我諗你睇左3log2?

6a
=(log32/log7)^2
=3.17

6b
=√(log2.5/log3-log0.8)
=0.965

7a
=[(logx^4)/(log6)][(log6)/(logx)]
=log4/logx

7c
=(log100/logx)(3logx)
=3*2
=6

9a
30^x=65.4
log(30^x)=log65.4
x=(log65.4)/log30
x=1.23

9b
25^(-x/6)=800
log[25^(-x/6)]=log800
-x/6=log800/log25
x=(log800/log25)(-6)
x=-12.5

10a
log(1-x)/2log3=1
log(1-x)=log8
1-x=8
x=-7

10b
log(2x+1)+log(1/5)=0
log(2x+1)(1/5)=0
(2x+1)/5=1
2x+1=5
2x=4
x=2

2012-03-31 15:31:18 補充：
corr
7a
[log(x^4)/log6](log6/logx)
=4logx/logx
=4

(1/2)[log(1-x)/log3]=1
log(1-x)=log9
1-x=9
x=-8