Simplify the following:

bobbym · 2014-09-02 01:20:39

Neither do I, there is a thing called completing the cube and I have post somewhere about it but I do not rememeber how I did it then. I use trial and error.

EbenezerSon · 2014-09-02 01:27:15

I know of completing the squre, can't it be possible if I use the quadratic formula?

Last edited by EbenezerSon (2014-09-02 01:28:03)

bobbym · 2014-09-02 01:28:12

The quadratic formula is for quadratics not cubics. One way is deflation.

EbenezerSon · 2014-09-02 01:33:53

The book has zero as the answer at the back

bobbym · 2014-09-02 01:41:04

That is one answer.

EbenezerSon · 2014-09-02 01:46:15

Yes, it is zero [0] that its answer at the back.

EbenezerSon · 2014-09-02 01:50:32

But I will try to invent completing the cubic formula from competing the square formula, and use it

bobbym · 2014-09-02 01:56:23

You do not have to that cubic is readily factorable.

EbenezerSon · 2014-09-02 03:33:22

I am stuck I can't do it

bobbym · 2014-09-02 03:42:43

Hi;

(m-1) (m^2+m-3)

EbenezerSon · 2014-09-02 03:43:09

I must learn how to factor cubics

bobbym · 2014-09-02 03:43:57

Have you learned how to graph functions?

EbenezerSon · 2014-09-02 03:49:02

Please sorry if I am bothering you much - if yok wouldn't mind I will like to learn your steps once and for all.

Thank you very much

bobbym · 2014-09-02 03:55:45

Have you learned how to graph functions?

EbenezerSon · 2014-09-02 09:25:31

bobbym wrote:

Have you learned how to graph functions?

No

(Sorry I was interrupted)

Last edited by EbenezerSon (2014-09-02 09:31:00)

bobbym · 2014-09-02 09:43:00

There is a formula for a cubic just like the quadratic one but it is much more involved.

EbenezerSon · 2014-09-03 17:40:05

Thanks Bobbym,
I wish I learn it! Because in case of any cubic equation I can't do it

Last edited by EbenezerSon (2014-09-03 17:43:15)

bobbym · 2014-09-03 20:02:33

Here is the method for completing the cube. It is a mess!

http://www.mathisfunforum.com/search.ph … 287574&p=2

EbenezerSon · 2014-09-05 06:30:14

Thank you
But the link could not open for me when I try it says "the search returned no hits" I don't understand why that.

But I would like to put this across, in fact the x^2 has me thinking about it,

Find the truth set of the equation;
3^(x^2 + 2) = 27^x

Last edited by EbenezerSon (2014-09-05 06:32:12)

bobbym · 2014-09-05 08:34:17

Howdy;

Take the log of the both sides.

You can solve for x from here.

EbenezerSon · 2014-09-06 01:02:43

Hi;

2logx - log3x + log2 = 0
x(2log10 - log3) = -log2
x = -log2/(2log10 - log3)

Is this correct?

Last edited by EbenezerSon (2014-09-06 01:05:10)

bobbym · 2014-09-06 02:14:51

The second line appears wrong. You can not just pull the x out of log(3x). In other words log(3x) does not equal x log(3).

EbenezerSon · 2014-09-06 05:49:54

Then see;

logx^2 - log3x + log2 =
log( x^2/3x) = -log2 > law of logarithm.
logx^2 = -log2*log3

Is this steps correct?

Last edited by EbenezerSon (2014-09-06 05:52:53)

bobbym · 2014-09-06 07:00:39

This is correct up to here:

EbenezerSon · 2014-09-06 09:32:22

In fact, I am stuck, please help.

Math Is Fun Forum

#426 2014-09-02 01:20:39

Re: Simplify the following:

#427 2014-09-02 01:27:15

Re: Simplify the following:

#428 2014-09-02 01:28:12

Re: Simplify the following:

#429 2014-09-02 01:33:53

Re: Simplify the following:

#430 2014-09-02 01:41:04

Re: Simplify the following:

#431 2014-09-02 01:46:15

Re: Simplify the following:

#432 2014-09-02 01:50:32

Re: Simplify the following:

#433 2014-09-02 01:56:23

Re: Simplify the following:

#434 2014-09-02 03:33:22

Re: Simplify the following:

#435 2014-09-02 03:42:43

Re: Simplify the following:

#436 2014-09-02 03:43:09

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#437 2014-09-02 03:43:57

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#438 2014-09-02 03:49:02

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#439 2014-09-02 03:55:45

Re: Simplify the following:

#440 2014-09-02 09:25:31

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#441 2014-09-02 09:43:00

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#442 2014-09-03 17:40:05

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#443 2014-09-03 20:02:33

Re: Simplify the following:

#444 2014-09-05 06:30:14

Re: Simplify the following:

#445 2014-09-05 08:34:17

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#446 2014-09-06 01:02:43

Re: Simplify the following:

#447 2014-09-06 02:14:51

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#448 2014-09-06 05:49:54

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#449 2014-09-06 07:00:39

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#450 2014-09-06 09:32:22

Re: Simplify the following:

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