Math Is Fun Forum

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Change your subject.

Make k the subject.

1/n = (k^+p^2/hg)^1/2

I have k=(hg/n^2-p^2) as the answer. But the book solved beyond my final solution,  and even had negative or positive sign in it.

please help me understand why its had that final answer, and as well how it came by the negative or positive sign.

Thanks in advance.
This is its final answer;

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I know only one thing - that is that I know nothing

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Change your subject.

Hi;

What comes after the k^?

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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.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Change your subject.

Is this your starting point?

If not, please modify this Latex so we know what the question is.

Thanks,

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Change your subject.

I'd say it's:

Or maybe with k and p both in the denominator.

Last edited by anonimnystefy (2013-08-04 10:40:32)

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“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Change your subject.

hi Stefy,

I'm sure you are right so here goes:

Ebenezerson:  That looks a bit like what you had.  But k is not yet the subject. We must deal with the square root:

Hope that is what you were wanting.

note: 

You must not just invert all the fractions to get

Try with numbers:

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Re: Change your subject.

The  'k' squared plus the 'p' squared are on one platform, which is over the 'hg'.
And all of them are in a square root sign.

Thanks.

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I know only one thing - that is that I know nothing

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Re: Change your subject.

Hi;

What comes after the k^?

"equal to sign" and after the sign, there is a "negative or positive  sign" which confound me much.

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I know only one thing - that is that I know nothing

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Change your subject.

I am curious, which answer did you like?

---

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.

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Re: Change your subject.

Make k the subject.

I had, k=(hg/n^2-p^2)

But the book has 1/n and a negative or positive sign after the "equl to sign", which is incomprehensible to me. Some help.

Please  solve it and you will definitly come across what I mean.

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I know only one thing - that is that I know nothing

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Change your subject.

Is post #4 the right problem?

---

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.

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Re: Change your subject.

No.
the k squared plus the p squared are on one platform, all over "hg". That's all,

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I know only one thing - that is that I know nothing

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Change your subject.

Hi;

Have you considered using codecogs? Then you would be able to latex the problem.

---

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.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Change your subject.

I'd say this is the problem:

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“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Re: Change your subject.

Bobbym, I cant found them at the bottom of the open window. There are few that are found there.

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I know only one thing - that is that I know nothing

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Change your subject.

Is post #13 the form 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.

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Re: Change your subject.

Yes, correcto perfecto.

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I know only one thing - that is that I know nothing

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Change your subject.

Hi;

The correct answers are:

---

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.

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Re: Change your subject.

the 'n' at the bottom carries a square why didnt you bring it?

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I know only one thing - that is that I know nothing

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Change your subject.

Sorry, I am not getting an n^2 just an n. I had Mathematica do that and he is never wrong.

---

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.

EbenezerSon

Member

Registered: 2013-07-04

Posts: 554

Re: Change your subject.

If we take it from the start. the n has to be squared when the square root at the R.H is taking away.

By the way what is mathematica I am curious to know.

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I know only one thing - that is that I know nothing

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Change your subject.

But, when you clear k of the square, you will be taking a square root, which means n will lose the square.

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Change your subject.

Yes, the n^2 will disappear.

Mathematica is a computer program that is smarter than 1001 mathematicians.

---

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.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Change your subject.

square both sides

times hg

subtract p squared

square root

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Change your subject.

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Change your subject.

Mathematica is a computer program that is smarter than 1001 mathematicians.

But just those 1001.  The rest of the mathematicians are still smarter. 

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob