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## #101 2017-01-19 04:37:22

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

### Re: Logical question s

What I do in this question plz tell

MZk

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## #102 2017-01-19 04:39:25

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Logical question s

First, for the 3rd time, get the formula for the surface area of the sphere.

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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## #103 2017-01-19 20:00:33

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

### Re: Logical question s

The surface area of a sphere is:

A=4pi r^{2}.

MZk

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## #104 2017-01-19 20:11:49

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Logical question s

If surface area of sphere is 100pi cm^2 , it's radius will be
5
10
25
50

Since you know A = 100 pi you can substitute into that formula.

Do you know what to do now?

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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## #105 2017-01-20 03:39:48

Mathegocart
Member
Registered: 2012-04-29
Posts: 1,884

### Re: Logical question s

Zeeshan, in the future, it would be preferable to try LaTeX or Codecogs so people can understand your statements.

The integral of hope is reality.

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## #106 2017-01-20 04:08:38

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Logical question s

Well said, Latex is possible DK's greatest contribution to man.

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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## #107 2017-01-20 20:58:56

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

### Re: Logical question s

Haha I really know  the formula but write 2 by mistake

Mathegocart hehe I think you people good in english so I wrote fast but you count every single statement
Next time I wrote complete question ok

MZk

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## #108 2017-01-20 21:05:07

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

Ans is 5

MZk

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## #109 2017-01-20 21:38:05

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Logical question s

r = 5 is correct.

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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## #110 2017-01-21 04:59:18

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

### Re: Logical question s

You know power series???

MZk

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## #111 2017-01-21 05:01:50

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Logical question s

Yes, I know lots of nice things about power series.

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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## #112 2017-01-22 03:41:38

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

Plz explain

MZk

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## #113 2017-01-22 03:45:52

zetafunc
Moderator
Registered: 2014-05-21
Posts: 2,124
Website

### Re: Logical question s

What would you like to have explained?

Last edited by zetafunc (2017-01-22 03:46:08)

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## #114 2017-01-22 03:52:22

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Logical question s

Plz explain

A power series can be thought of as a polynomial of infinite degree. The field is huge so you will have to narrow the questiion down. In computation, we use them often.

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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## #115 2017-01-25 04:30:54

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

### Re: Logical question s

Means???.
computation, we use them often.

MZk

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## #116 2017-01-25 04:52:40

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Logical question s

Polynomials are something we know a lot about. They are easy to compute, they have nice derivatives and integrals, we can find the roots numerically, they are faster for computers. Transcendental functions like e^x are another matter.

For instance if we have x^2 - 2x + 1 and x = 1 anybody who has some algebra can tell us the 1^2 - 2(1) + 1 = 0.

But if I ask what is e^x when x = 1? It is not so easy. To get that we use power series ( among other methods ).

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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## #117 2017-01-27 15:22:33

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

### Re: Logical question s

Hmm e^x at 1 is difficult to compute so which series used

MZk

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## #118 2017-01-27 16:01:48

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Logical question s

The power series for e^x of course.

Notice that e^x has been replaced by powers of x.

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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## #119 2017-02-02 01:51:19

Member
From: Planet Mars
Registered: 2016-11-15
Posts: 739

### Re: Logical question s

Hi here are all the answers.

Last edited by iamaditya (2017-02-06 23:31:17)

Practice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam

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## #120 2017-02-17 01:17:20

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 648

Kk

MZk

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