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#101 Re: Help Me ! » Simplify the following: » 2014-10-21 04:14:47

Wow!
I confronted a math tutor - but he claimed the answer 1/3 or -1/3 is correct - now I Could realise that your method is good. Please I want the tutor to see for himself your steps because he was insisting that the books' answer is correct

Thanks bobbym

#102 Re: Help Me ! » Simplify the following: » 2014-10-21 03:58:49

Yes that's the problem - I copied it correctly.

When you plug in your answers does it give 1?

#104 Re: Help Me ! » Simplify the following: » 2014-10-20 04:55:26

Hi, Bobbym, I was called away, I am sorry - but I don't have my calculator with me now.
It is negative or positive 1/3 in the book as an answer. When I get to  the house I will punch them in the calculator and see if it really gives negative or positive 1/3.

#107 Re: Help Me ! » Simplify the following: » 2014-10-20 00:08:09

bobbym wrote:

Are we talking about log(x+1) - 2logx^2 = 1?


Yes.

#108 Re: Help Me ! » Simplify the following: » 2014-10-19 18:06:08

The book tells that, if the base is not written then it in base 10. What do say? Again, are you saying it is a wrong answer?

[the book solved it]

#109 Re: Help Me ! » Simplify the following: » 2014-10-17 08:12:51

log(x+1) - 2logx^2 = 1
log(x+1/x^2) = log10
Anti-log taking at both sides
x + 1 = 10x^2
9x^2 = 1
x^2 = 1/9
x = +1/3
This method is quite understandable to me, but to my suprise I can not use it to solve the one under discussion literally for many days

#110 Re: Help Me ! » Simplify the following: » 2014-10-16 19:07:15

In fact, I am well familiar with my method - but unfortunately I can't arrive on 1/4 as the answer

#111 Re: Help Me ! » Simplify the following: » 2014-10-14 09:22:55

bobbym wrote:

Divide both sides by - 3

and the rest is easy.


Please - continue I am not getting the answer

#112 Re: Help Me ! » Simplify the following: » 2014-10-04 07:01:08

Hi;
please - show the steps of my idea too.

#113 Re: Help Me ! » Simplify the following: » 2014-10-04 06:54:04

I am very sure if I see your steps would help me know how to go about a similar problem.

#114 Re: Help Me ! » Simplify the following: » 2014-10-04 06:31:13

Please, if you would not mind use my idea to solve, because I am rather familiar with that idea.

Thank you very much

#115 Re: Help Me ! » Simplify the following: » 2014-10-04 06:20:26

Okay, I will let you see that problem yourself.

In one of the rules of logarithm it says, log(m/n) equal log m - log n, so I was expecting you would say logx - 4logx would be log(x/x^4). But couldn't understand why you subtracted logx from 4logx.

#116 Re: Help Me ! » Simplify the following: » 2014-10-01 21:03:38

There was a similar problem in the book, and there was 1 at the right hand side of the equation,  and in the course of manipulation it became [log10] and when antilog was taken it became 10. So that's the idea I tried using it. I don't know if you understand what I am putting across.

Hi; this is the problem I spoke of above, that used the one I understand;

log(x^2 + 1 ) - 2logx = 1
log(x^ + 1/ x^2) = log10
x^ + 1/x^2 = 10
x^2 + 1 = 10x^2
9x^2  = 1
x^2 = 1/9
x = +1/3

Please, see the method - this is the one I wanted to use for the one under discussion

#117 Re: Help Me ! » Simplify the following: » 2014-10-01 04:55:46

bobbym wrote:

Where does log8^2 come from?

That's according to the difinition of logarithm
- "the logarithm of any number b to the base a is the index or power to which the base must be raised to give the number" example ; 
log b = c [taking 'a' as the base] =  b = a^c

#118 Re: Help Me ! » Simplify the following: » 2014-09-30 04:42:51

If so, then I was thinking the steps should be;

logx - 4logx = 2
log(x/x^4) = log8^2
taking antilog of both sides
x/x^4 = 8^2
x = 64x^4

What do you say to this?

#119 Re: Help Me ! » Simplify the following: » 2014-09-30 02:37:21

I see now, but do you agree that a minus sign in logarithm means one has to divide?

#120 Re: Help Me ! » Simplify the following: » 2014-09-29 01:42:13

bobbym wrote:

logx - 4logx = 2


I'm now grasping it - how are you gonna proceed from here?

#121 Re: Help Me ! » Simplify the following: » 2014-09-29 01:12:45

How I did it was;

log(x/x^4) = 8^2
taking antilog
x = 64x^4

[I was rather thinking that minus sign in logarithm means a division sign, what do you say to this?]

#122 Re: Help Me ! » Simplify the following: » 2014-09-29 01:00:19

bobbym wrote:

logx - 4logx = 2


wierd to me though

#124 Re: Help Me ! » Simplify the following: » 2014-09-28 23:39:52

Is 8  not going to raise the power 2 at the RHS?

#125 Re: Help Me ! » Simplify the following: » 2014-09-28 04:47:59

Now before I proceed on the decimals, let me endeavour to put this across c'os I am getting zero as an answer to this and the book seems to have 1/4 ;

logx - 4logx = 2

The LHS is having 8 as their bases

Thank you!

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