Jump to content
BrainDen.com - Brain Teasers
  • 0

When is 0 / 0 =1 ? : Solution Posted


Guest
 Share

Question

When can the following be true?

0 / 0 = 1

Yes, read as zero divided by zero equals one!

No Tens, unit, magic.. blah blah! guess enuff hint for now

Finally the solution:

dBm is a unit to measure absolute Power, x dBm = 10* log(X^10e+3), where X is power in Watts.

Thus, 1 mw (milli Watt) = 10e-3 W = 10 * log(1) dBm = 0 dBm

Now, 0 (in dBm) / 0 (in dBm) = 1 (but Obvious)

So fellas, spot any fallacies?

Gee, should acknowledge some guy in SD for some funny questions on dBm scale which led to this q. Me thinks it makes cracker of a q

Link to comment
Share on other sites

  • Answers 56
  • Created
  • Last Reply

Top Posters For This Question

Recommended Posts

  • 0

a = 1

a = b

a^2 = ab

a^2 - b^2 = ab - b^2

(a+B.) (a-B.) = b(a-B.)

divide through by a-b

(a+B.) = b

a + b -1 = b-1

1 + 1 - 1 = 1-1

1 = 0

so

0/0 = 1

is the same as

0/1 = 0

and therefore the answer is always.

Link to comment
Share on other sites

  • 0

Yeah I know - I was kidding with that one. When I was in school one of my profs challenged us to prove 25 incorrect mathematical concepts such as ln 1 = 0; 0=1; i squared = 1;....

I won.

Link to comment
Share on other sites

  • 0

Skale. This may not be the answer you were looking for but I stand by the mathematices of this.

The answer to any number to the power of 0 = 1.

(try typing the equation 0 to the power 0 (ie 0^0=) into google for example and see what answer it gives).

Texts on the matter call the equation, the 'indeterminate form'. But all perceived wisdom accepts 0^0=1

Link to comment
Share on other sites

  • 0
Skale. This may not be the answer you were looking for but I stand by the mathematices of this.

The answer to any number to the power of 0 = 1.

(try typing the equation 0 to the power 0 (ie 0^0=) into google for example and see what answer it gives).

Texts on the matter call the equation, the 'indeterminate form'. But all perceived wisdom accepts 0^0=1

That's just bad programming which doesn't test the 0 base along with the 0 exponent. 0 raised to any non-negative exponent (except 0) is 0, and any number raised to the 0 power (except 0) is 1, but it's just easier to do those tests separately than together. So 0^0 ends up being 1, even though that's mathematically incorrect.

And Skale, if you know what an indeterminate form is, then you should also realize that 0/0 is also an indeterminate form. As is infinity/infinity, infinity - infinity, etc etc.

Link to comment
Share on other sites

  • 0
That's just bad programming which doesn't test the 0 base along with the 0 exponent. 0 raised to any non-negative exponent (except 0) is 0, and any number raised to the 0 power (except 0) is 1, but it's just easier to do those tests separately than together. So 0^0 ends up being 1, even though that's mathematically incorrect.

And Skale, if you know what an indeterminate form is, then you should also realize that 0/0 is also an indeterminate form. As is infinity/infinity, infinity - infinity, etc etc.

Thanks, you are correct as to 0/0 by itself is indeterminate form... that is another hint! But you shall see when I reveal the answer (or unless someone thinks of it...). Btw, I have submitted it somewhere and yet to hear back on it!

Link to comment
Share on other sites

  • 0
When can the following be true?

0 / 0 = 1

Yes, read as zero divided by zero equals one!

No Tens, unit, magic.. blah blah! guess enuff hint for now

The answer is never

He did not say that is was true - he asked when can it be true.

Link to comment
Share on other sites

  • 0
The answer is never

He did not say that is was true - he asked when can it be true.

No, there is way! Am claiming a very neat and simple solution for this one..

Link to comment
Share on other sites

  • 0

0 = 0 + 0 +0 + 0 + 0 +0 +0 ....

0 = (1 + -1)

0 = (1 + -1) + (1 + -1) +(1 + -1) ...

associtive property

0 = 1 + (-1 + 1) + (-1 + 1) + (-1 + 1)....

-1 + 1 = 0

0 = 1 + 0 + 0...

0 = 1

Link to comment
Share on other sites

  • 0

O = 1... O/O = 1... ta daa

but seriously

Im not sure if someone mentioned this already but...

0^0/0^0 = 1

the ^0 should cancel out so ((0^0)^1/0)/((0^0)^1/0) = 0/0 = 1

Link to comment
Share on other sites

  • 0
O = 1... O/O = 1... ta daa

but seriously

Im not sure if someone mentioned this already but...

0^0/0^0 = 1

the ^0 should cancel out so ((0^0)^1/0)/((0^0)^1/0) = 0/0 = 1

I though of that one....but 0^0 is defined as "undefined" so the ans is undefined/undefined

Link to comment
Share on other sites

  • 0

the sign / can also mean a fraction and if there is the same number on either side of it like a zero on e eaiter side of it or a two on either side of it makes ONE whole so, zero over zero equals one whole, I think

Link to comment
Share on other sites

  • 0

There may be another answer, 0dBu/0dBu=1;

u-->unit

because....0dB=10 (or 20) log 1u

so, log1u/log1u=1;

but obviously i makes no sense...when you are talking of x=y=z=.....you should compare in same scale.

Link to comment
Share on other sites

  • 0
When can the following be true?

0 / 0 = 1

Yes, read as zero divided by zero equals one!

No Tens, unit, magic.. blah blah! guess enuff hint for now

Finally the solution:

dBm is a unit to measure absolute Power, x dBm = 10* log(X^10e+3), where X is power in Watts.

Thus, 1 mw (milli Watt) = 10e-3 W = 10 * log(1) dBm = 0 dBm

Now, 0 (in dBm) / 0 (in dBm) = 1 (but Obvious)

So fellas, spot any fallacies?

Gee, should acknowledge some guy in SD for some funny questions on dBm scale which led to this q. Me thinks it makes cracker of a q

I need some help understanding this one...

What is the claimed obviousness of 0 (in dBm) / 0 (in dBm) = 1?

Decibels are logarithms of power ratios: you take ratios of power values, then take log to get dB values.

Then, you add and subtract dB values to conveniently express multiplicative power gains and losses, respectively.

Which leaves me wondering ...

[1] why are you dividing [instead of subtracting] two decibel numbers

[2] what is the physical significance of ratios of decibel values and

[3] where is the obviousness that attaching units to 0's makes their ratio unity? :huh:

What I do understand is 0[dBm] - 0[dBm] = 0. Meaning the ratio of two 1-mW signals is 1, whose log is 0.

I think someone sold you an interesting story ... B))

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Answer this question...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...