You need to use logarithm and exponential laws for this.
Please help!
Solve for x: 3^x = 15?
2009-03-10 11:44 am
回答 (5)
2009-03-10 11:48 am
✔ 最佳答案
3^x = 15log(3^x)=log(15)
xlog3 = log15
x = log15/log3
2009-03-10 6:50 pm
3^x = 15
xln(3)=ln(15)
x=ln(15)/ln(3) answer//
xln(3)=ln(15)
x=ln(15)/ln(3) answer//
2009-03-10 7:08 pm
3^x = 15
log(3^x) = log(15)
(x)log(3) = log(15)
x = log(15)/log(3)
log(3^x) = log(15)
(x)log(3) = log(15)
x = log(15)/log(3)
2009-03-10 6:52 pm
From your original expression we get
xlog3 = log15
So x = log15/log3 Get the logs from Excel or a book of tables
Then x = 1.1761/0.4771 using logs base-10
And so x = 2.4650 to 4 decimal places
Check: 3^2.4650 = 15 using Excel
xlog3 = log15
So x = log15/log3 Get the logs from Excel or a book of tables
Then x = 1.1761/0.4771 using logs base-10
And so x = 2.4650 to 4 decimal places
Check: 3^2.4650 = 15 using Excel
2009-03-10 6:50 pm
xlog3=log3+log5
(x-1)log3=log5
x=log5/log3+1=2.465
(x-1)log3=log5
x=log5/log3+1=2.465
收錄日期: 2021-05-01 12:07:14
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