Questions on Algebra: Logarithm answered by real tutors!

Tutors Answer Your Questions about logarithm (FREE)

Question 47037: ln (x + 5) - ln x =(4/3)
Click here to see answer by uuuu(3)

Question 47048: A bacteria culture started with a count of 480 at 8:00 A.M. and after t hours is expected to grow to f(t)=480(3/2)^t. Estimate the number of bacteria in the culture at noon the same day.
Thanks.
Click here to see answer by Nate(3500)

Question 47049: The decibel level of sound is given by D=10*log(I/10^-12), where I is the sound intensity measured in watts per square meter. Find the decibel level of a whisper at an intensity of 5.4 x 10^-10 watts per square meter.
Click here to see answer by Nate(3500)

Question 47047: The population P of a certain culture is expected to be given by a model P=100e^rt where r is a constant to be determined and t is a number of days since the original population of 100 was established. Find the value of r if the population is expected to reach 200 in 3 days.
Thank you.
Click here to see answer by Nate(3500)

Question 47087: Express as a single natural log: 2lnx + 4lny -5lnz
Click here to see answer by mathchemprofessor(65)

Question 47161: need help solving log subscript 3(10x-1) - log subscript 3(x)=2
Click here to see answer by Nate(3500)

Question 47180: Expand: Log2 8xy
Click here to see answer by adamchapman(301)

Question 47179: Express the logarithm in a simplified form?
3lnx-2lny-4lnz
Click here to see answer by adamchapman(301)

Question 47368: Help Please.
Use the change of base rule to find the logarithm to four decimal places.
log8 0.78
Click here to see answer by Nate(3500)

Question 47374: Hi again,
I could use soem help in seeing how this problem is worked out:
2^x-6=8^x
Thanks again,
Lous
Click here to see answer by Nate(3500)

Question 47445: I have problems with logs please help
log4 (x - 2) + log4 (x - 2) = 1
Click here to see answer by longjonsilver(2297)

Question 47446: Help
log5 x = 3
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Question 47509: proof Loga X=Y
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Question 47609: Rewrite the expression as a sum or difference or multiple
log^2(x^6y^7/4)
Click here to see answer by Nate(3500)

Question 47756: Simplify: 2log(base4)9 - log(base2)3
Click here to see answer by stanbon(57282)

Question 47762: slove
log6 4x-log6 (x-3)=log6 12

Click here to see answer by stanbon(57282)

Question 47771: Given that log (lower a)(x)=3.58 and log (lower a) (y)= 4.79, find log (lower a)(y/x).
I can not figure out these logarithms. Please help. Test coming soon.
Click here to see answer by stanbon(57282)

Question 47447: Write in logarithmic form
2^-2 = 1/4
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Question 47779: Using a calculator, find log 1000 where log means log to the base of 10.
Click here to see answer by stanbon(57282)

Question 46867: solve for x
log2(x+2) + log2x=3
Click here to see answer by consc198(59)

Question 47866: Most calculators have 2 different logs on them: log, which is base 10, and In which is base e. In computer science, digital computers are based on the binary numbering system which means that there are only 2 numbers available to the computer, 0, and 1. When a computer scientist needs a logarithm, he needs a log to base 2 which is not on a calculator. To find the log of a number to any base, we can use a conversion formula as shown here: ?
Click here to see answer by stanbon(57282)

Question 47879: Ok, in conjunction of question 47866, using this formula below:
log b a =
log a
_____
log b
Using this formula, find log 2 1000. Round your answer to the hundredth's place.
(NOTE: the b in log b a is small as well as the 2 in log 2 1000) Hope that makes sense.
Click here to see answer by stanbon(57282)

Question 47888: expand the expression log sub script 4 32x
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Question 47887: ln sqrt x-2 = -2
Click here to see answer by Nate(3500)

Question 47887: ln sqrt x-2 = -2
Click here to see answer by stanbon(57282)

Question 47886: Why is a 7.0 earthquake ten times stronger than a 6.0 earthquake?
Click here to see answer by stanbon(57282)

Question 47886: Why is a 7.0 earthquake ten times stronger than a 6.0 earthquake?
Click here to see answer by tsmith5651(7)

Question 47885: What is the formula for measuring earthquakes?
Click here to see answer by stanbon(57282)

Question 47369: Use the change of base rule to find the logarithm to four decimal places.
log4.6 22
Click here to see answer by Nate(3500)

Question 48065: solve Log(a)(7x+1)= Log(a)(4x+16)
where both sides are multiplied by Log(a) can't i really just ignore that and
solve the equation 7x+1=4x+16
which reduces to 3x=15 so x=5?
Click here to see answer by atif.muhammad(135)

Question 47979: write as a single logarithm
5Lnx-81Lny

solve for x
4Ln(3x)=40
10x+3=102

expand 1og(x raised to the 3rd power) divided by 10,000
5-x+2=5 3x+7
Click here to see answer by Nate(3500)

Question 48091: Find the number log5(1/5).
My possible answers are:
a. -5
b. -1
c. 0.2
d. 1
Thank you for your help.
Click here to see answer by Nate(3500)

Question 48140: Not sure how to do the algebra or calculator part to solve composite functions.

Click here to see answer by tutorcecilia(2152)

Question 48217: I am trying to answer a question that reads: "Explain the difference between a logarithm of a product and the product of logarithms and give examples of each" I understand the product of a logarithm is the sum of the logarithm however I do not understand the difference?

Click here to see answer by stanbon(57282)

Question 48260: would really appreciate help on this one!
solve for x:
2log[base 4]x-log[base 4](x-1)=1
Click here to see answer by stanbon(57282)

Question 48256: Express Logarithm as a single quantity:
4[lnx-7ln(x-2)]-5ln(x+2)
=4[lnx/(x-2)^7] - ln(x+2)^5
=ln[(lnx^4/(x-2)^28]/(x+2)^5]

Click here to see answer by stanbon(57282)

Question 48672: I need help in finding the value of X:
log2 8 = x
Click here to see answer by longjonsilver(2297)

Question 48803: Solve for x exactly. Do not use calculator or table show work.
In (log x)=1
Click here to see answer by stanbon(57282)

Question 48986: write the logarithmic equation in exponential form
log 3 27 = 3
log 125 25 = 2/3
Click here to see answer by Nate(3500)

Question 48985: convert to logarithmic equations
16 ^3/2 = 64
e^x = 5
Click here to see answer by Nate(3500)

Question 49208: Solve for x: log(4x^2)-log(16x)=1

Click here to see answer by longjonsilver(2297)

Question 49211: 5^2x-1=27.6
solve for x

Thank you, Michelle
Click here to see answer by AnlytcPhil(1276)

Question 49211: 5^2x-1=27.6
solve for x

Thank you, Michelle
Click here to see answer by atif.muhammad(135)

Question 49138: Sir, if you please sent me formulas of calculas,trignomentry,algebra e.t.c
Click here to see answer by atif.muhammad(135)

Question 49307: 4e^(3x-1)=46
Click here to see answer by Nate(3500)

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