maths

🎓 學業台小學及中學教育

[匿名]

2006-10-31 12:33 am

解方程:2^x+1–2^x-1=12

答案係3
我想要個式
唔該

回答 (2)

[匿名]

2006-10-31 12:46 am

✔ 最佳答案

(2^(x+1))/2^x - (2^(x - 1))/2^x = 12/(2^x)

2^1 - 2^-1 = (2^(2)*3)/2^x

3/2 * 1/3 = (2^2)/2^x

1/2 = (2^2)/2^x

2^x = 2^3

therefore,x = 3

參考: me

👍 0 👎 0

wongkamfai

2006-10-31 2:36 am

(2^(x+1))/2^x - (2^(x - 1))/2^x = 12/(2^x)

2^1 - 2^-1 = (2^(2)*3)/2^x

3/2 * 1/3 = (2^2)/2^x

1/2 = (2^2)/2^x

2^x = 2^3

參考: me

👍 0 👎 0