更新1:
the equation is 8^(2x-5)=5^(x+1)
How to I solve 8^2x-5 = 5^x+1 using logarithm equation. Please show the steps if you can.?
回答 (4)
2016-06-06 9:24 pm
8^(2x - 5) = 5^(x + 1)
log[8^(2x - 5)] = log[5^(x + 1)]
(2x - 5) log(8) = (x + 1) log(5)
2x log(8) - 5 log(8) = x log(5) + log(5)
2x log(8) - x log(5) = 5 log(8) + log(5)
x [2 log(8) - log(5)] = 5 log(8) + log(5)
x = [5 log(8) + log(5)] / [2 log(8) - log(5)]
x ≈ 4.709513175
log[8^(2x - 5)] = log[5^(x + 1)]
(2x - 5) log(8) = (x + 1) log(5)
2x log(8) - 5 log(8) = x log(5) + log(5)
2x log(8) - x log(5) = 5 log(8) + log(5)
x [2 log(8) - log(5)] = 5 log(8) + log(5)
x = [5 log(8) + log(5)] / [2 log(8) - log(5)]
x ≈ 4.709513175
2016-06-06 9:19 pm
If you mean 8^(2x - 5) = 5^(x + 1), take logs of both sides to get
(2x - 5) log 8 = (x + 1) log 5
and that is just a linear equation in x.
If you mean 8^(2x) - 5 = 5^x + 1, I don't think this can be solved analytically. You would need to use approximate numerical methods.
(2x - 5) log 8 = (x + 1) log 5
and that is just a linear equation in x.
If you mean 8^(2x) - 5 = 5^x + 1, I don't think this can be solved analytically. You would need to use approximate numerical methods.
2016-06-06 9:16 pm
Maybe you mean
8^(2x - 5) = 5^(x + 1).
If you do mean that, you must NOT write it without the parentheses, as that means something completely different.
(2x - 5)*log(8) = (x+1)*log(5) =>
(2x - 5)(0.903) = (x+1)(0.699) =>
1.806 x - 4.515 = 0.699 x + 0.699 =>
1.107 x = 5.214 =>
x = about 4.7 but use a calculator.
8^(2x - 5) = 5^(x + 1).
If you do mean that, you must NOT write it without the parentheses, as that means something completely different.
(2x - 5)*log(8) = (x+1)*log(5) =>
(2x - 5)(0.903) = (x+1)(0.699) =>
1.806 x - 4.515 = 0.699 x + 0.699 =>
1.107 x = 5.214 =>
x = about 4.7 but use a calculator.
2016-06-06 9:02 pm
Do you mean
8^(2x) - 5 = 5^x + 1
or maybe
(8^2) x - 5 = 5^x + 1
or maybe
8^(2x-5) = 5^x + 1
or maybe
8^(2x-5) = 5^(x+1)
?????????
8^(2x) - 5 = 5^x + 1
or maybe
(8^2) x - 5 = 5^x + 1
or maybe
8^(2x-5) = 5^x + 1
or maybe
8^(2x-5) = 5^(x+1)
?????????
收錄日期: 2021-05-01 13:07:36
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