中4數學,唔該大家列詳細既步驟.我驚睇唔明.唔該 大家

1. 22x=64
2xlog2=log64
2xlog2=6log2
2x=6
x=3

2. (32x-9)2=0
32x-9=0
32x-32=0
(3x+3)(3x-3)=0
3x=-3 or 3x=3
xlog3=log-3(rej.) or xlog3=log3
x=1

2^2x=64
2^2x=2^6(--->64)
2x=6----拆個基數2
x=3

(3^2x-9)^2=0
3^2x-9=0(開方(0)=0)
3^2x=9
3^2x=3^2(3*3=9,明啦)
2x=2----拆個基數3
x=1

2^2x=64
2^2x=2^6
therefore : 2x=6
x=3



(3^2x-9)^2=0
每邊開方.. (3^2x-9)=0
(3^2x-3^2)=0
運用公式..(3+2x)(3-2x)=0
x=3/2 or x=-3/2

2008-05-14 22:12:53 補充：
睇錯題目=口=

(3^2x-9)^2=0
每邊開方.. (3^2x-9)=0
(3^2x-3^2)=0
運用公式..(3^x-3)(3^x+3)=0
3^x=3 or 3^x=-3(rejected)因為3冇邊個次方系會出-數=口=
x=1...