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#1 Re: Help Me ! » Solving Logarithms » 2008-04-19 06:59:36

I'm not sure how I would do that on my calculator b/c it's a hp 9g graphing calculator. Is there another way to simplify it more to get the answer?

#2 Re: Help Me ! » Solving Logarithms » 2008-04-19 06:43:56

My book says the answer is 0.466

#3 Re: Help Me ! » Solving Logarithms » 2008-04-19 04:46:15

I get x^3+2x^2+x-1 right? And then what?

#4 Re: Help Me ! » Solving Logarithms » 2008-04-19 03:46:09

Kurre wrote:

use the fact:

I can get to that part but I don't know what to do after that.

#5 Help Me ! » Solving Logarithms » 2008-04-19 02:12:16

angelus2402004
Replies: 20

I need help with figuring out how to solve these two problems.

1: logbase7(1-x)-logbase7(x+2)=logbase7x^2
2: logbase3(2-x)-logbase3(x+3)=logbase3x

Thank you.

#6 Re: Help Me ! » Another Logarithmic Equation problem » 2008-03-24 05:48:47

LuisRodg wrote:

I was trying to solve the one you put before and you edit it out? Why do you do that? I dont feel like wasting my own time to help you and then you edit it out.

Good luck.

Sorry. It was the wrong problem that I needed help with.

#8 Re: Help Me ! » Another Logarithmic Equation problem » 2008-03-24 05:33:06

Do you know how I would set up this equation to solve it?

lN(INx) = 1

#9 Re: Help Me ! » Another Logarithmic Equation problem » 2008-03-24 05:22:23

The only way that I got 2.177 was putting in parenthesis around only SQRT ((In42) + 1) and I got the answer from the book.

#10 Re: Help Me ! » Another Logarithmic Equation problem » 2008-03-24 05:11:23

What answer did you get? The book says +- 2.177

#12 Re: Help Me ! » Help Solving Logarithmic Equations » 2008-03-20 05:22:22

Thank You!!

John E. Franklin wrote:

- - 13 PlusOrMinusForTwoAnswers SquareRootOF[13^2 - 4(6)(6 - 10^(3/2)] all over 2(6) = x

+13 PlusOrMinus SquareRootOf{169 - (4)(6)(6) - - (4)(6)(10^[3/2])} all over 12 = x

13 PlusOrMinus SquareRootOf{169 - (4)(36) + (24)(10^[3/2])} all over 12 = x

13 PlusOr Minus SquareRootOf{169 - (2)(72) + (24)(1000^[1/2])} all over 12 = x

24 times 24 is 576, which is (3)(2)(2)(2) squared, oh forget that, put it in and back out of 1000 doesn't help.

1000 is (5)(2)(5)(2)(5)(2), so two 5's and and two 2's can come out of the 1000^(1/2).

1000^(1/2) = (5)(2) [(5)(2)]^{1/2} => 10 squareRoot(10)

13 PlusOrMinus SquareRootOf{169 - (2)(72) + (24)(10)(10^[1/2])} all over 12 = x

2 times 72 = 144,   169 - 144  is 25.

13 PlusOrMinus SquareRootOf{25 + 240(10^[1/2])} all over 12 = x

I don't know how to simplify it anymore, but if
you just use your calculator, you can get an
approximation.

x = -1.249920592 the Right Answer because I plugged it back in.

.759649851 + .740350148 = 1.5

The other answer of x = 3.416587258 is WRONG because if you plug it into original problem,
it goes negative inside the logarithms.

#13 Re: Help Me ! » Help Solving Logarithmic Equations » 2008-03-20 05:20:48

LuisRodg wrote:

logbase7(1-x) - logbase7(x+2) = logbase7(x^2)

logbase7((1-x)/(x+2)) = logbase7(x^2)
(1-x)/(x+2) = x^2
x^3 + 2x^2 + x - 1 = 0
x = 0.465571231877

How do I find x?

#14 Help Me ! » Help Solving Logarithmic Equations » 2008-03-20 02:59:58

angelus2402004
Replies: 13

I need help trying to figure out how to solve these step by step please

log (2-3x) + log (3-2x) = 1.5

logbase7(1-x) - logbase7(x+2) = logbase7(x^2)


Thank You!

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