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log(y^2/2x) = log2y-log2x
The right hand side of that is incorrect.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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it's log2(y-x)
I multiplied log2 with what is in the bracket, to have that. Why you say so.
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Hi;
Because when you write
log2y-log2x
how do you know which of these is what you want
log(2)*y or log(2y)?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Errr, I dont normally put bracket around figures as you normally do.
But I suppose each of them are the same, I mean what yours above.
In #229
I know only one thing - that is that I know nothing
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Errr, I dont normally put bracket around figures as you normally do.
Math has to be precise. More precise than anything else you do.
When you write log2x, no one can figure out what you mean. It appears you wanted log(2)x, but I am not sure. Which do you want?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Thanks, Bobbym.
Then please let me how it should be
By the way I have developed the attitude of not putting brackets c'os the book I have doesn't put it around each example it gives. And that has become of me.
I know only one thing - that is that I know nothing
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Hi;
In post #225 you wrote this
log(y^2/2x) = log2y-log2x
Please use brackets to tell me what you want on the right hand side.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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But Bobbym I havent envisioned that bracket of the right hand side could cause any thing, but I think;
Log2(y-x) = log2y-log2x
I think is the same as, log(2y)-log(2x)
Please help if I am confused.
I know only one thing - that is that I know nothing
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Okay, we have the original problem looking like this
If 2logy-log2x=2log(y-x), express y in terms of x. I had (y-x)(y-2x^2). The book has y^-4xy+4^2x=0.
Hold on while I work on it. The book answer is okay but it is not an answer to the question
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Oops. Bobym.
Please I made a little blunder!
2logy-log2x=log2(y-x).
I know only one thing - that is that I know nothing
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So you want this?
It looks a lot like the earlier one.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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2logy-log2x=log2(y-x)
express y in terms of x.
This how is in the book.
Thanks.
I know only one thing - that is that I know nothing
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That book is awful.
Mathematics uses brackets to avoid ambiguities.
I will interpret it as:
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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But is the answer I had the same as yours when you solved?
I am using my phone to browse and the battery has run low.
I know only one thing - that is that I know nothing
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Those are all correct answers with methods shown.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Is your interpretation the ones the book should have used?
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Let's see what happens.
10^ to both sides
Multiply both sides by 2x
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Hi EbenezerSon
With a careful look at signs I think should be,
x-3x-3-3/x^2-9 =
-2x-6/x^2-3^2 =
-2(x+3)/(x-3)(x+3)
= -2/x-3
Please am I right there.
Thanks.
I know only one thing - that is that I know nothing
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I am getting
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Oops,
I have considered it once more and I could see Anonymstify is right with his answer, I lost sight with some negative sign, here
x+3-3(x-3) = x+3-3x+3.
=-2x+6
Bobbym, I suppose you lost sight on a negative sign. With a careful check you will adentify it.
I know only one thing - that is that I know nothing
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Hi;
I am sorry but my answer is correct.
Please check post #244, in line 2 there is an error.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Please could you demostrate to me?, c'os I can't adentify it.
I know only one thing - that is that I know nothing
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How did 3(x+1) become 3x-3?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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I see, then let me check the original one and come back.
I know only one thing - that is that I know nothing
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