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Default How to determine the value?

Power(2,a) = 1,
Does anyone have any suggestions on how to determine the value of a?
Thank for any suggestions
Eric
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Default How to determine the value?

0
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Gary''s Student - gsnu200737


"Eric" wrote:

Power(2,a) = 1,
Does anyone have any suggestions on how to determine the value of a?
Thank for any suggestions
Eric

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Default How to determine the value?

The answer to your immediate question is 0 but I guess that's just indicative
of a more general question.

How about using Solver
Put this in a cell

=2^A1

and solve for that cell to the value you know by changing A1

Mike

"Eric" wrote:

Power(2,a) = 1,
Does anyone have any suggestions on how to determine the value of a?
Thank for any suggestions
Eric

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Default How to determine the value?

On Aug 15, 6:08 am, Eric wrote:
Power(2,a) = 1,
Does anyone have any suggestions on how to determine the value of a?


More generally, if power(b,x) = n, then x = log(n) / log(b). But
beware of inaccuracies introduced by the computational error that is
inherent in computer arithmetic. Always check to see if power(b,x)
truly is n.

PS: You can replace power(2,a) with 2^a. One less (nested) function.

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Default How to determine the value?

Or use some algebra:

=Power(2,a)
is the same as
2^a (2 raised to the power of a

The equality to start
2^a = 1
taking the natural log of both sides:
ln(2^a) = ln(1)
the left hand side becomes: a*ln(2)
the right hand side becomes 0
so
a*ln(2) = 0
divide both sides by ln(2)
a = 0/ln(2)
or
a = 0

=====
So if you had
=power(2,a) = x
you could do the same thing
2^a = 1
taking the natural log of both sides:
ln(2^a) = ln(x)
the left hand side becomes: a*ln(2)
so
a*ln(2) = ln(x)
divide both sides by ln(2)
a = ln(x)/ln(2)



Eric wrote:

Power(2,a) = 1,
Does anyone have any suggestions on how to determine the value of a?
Thank for any suggestions
Eric


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Dave Peterson


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Default How to determine the value?

You don't need to use Solver.
The formula for a =LOG(1)/LOG(2)
--
David Biddulph

"Mike H" wrote in message
...
The answer to your immediate question is 0 but I guess that's just
indicative
of a more general question.

How about using Solver
Put this in a cell

=2^A1

and solve for that cell to the value you know by changing A1


"Eric" wrote:

Power(2,a) = 1,
Does anyone have any suggestions on how to determine the value of a?
Thank for any suggestions
Eric



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Default How to determine the value?

.... or of course simply =LOG(1,2)
--
David Biddulph

"David Biddulph" <groups [at] biddulph.org.uk wrote in message
...
You don't need to use Solver.
The formula for a =LOG(1)/LOG(2)


"Mike H" wrote in message
...
The answer to your immediate question is 0 but I guess that's just
indicative
of a more general question.

How about using Solver
Put this in a cell

=2^A1

and solve for that cell to the value you know by changing A1


"Eric" wrote:

Power(2,a) = 1,
Does anyone have any suggestions on how to determine the value of a?
Thank for any suggestions
Eric





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Default Thank everyone for suggestions

Thank everyone for suggestions
Eric

"Dave Peterson" wrote:

Or use some algebra:

=Power(2,a)
is the same as
2^a (2 raised to the power of a

The equality to start
2^a = 1
taking the natural log of both sides:
ln(2^a) = ln(1)
the left hand side becomes: a*ln(2)
the right hand side becomes 0
so
a*ln(2) = 0
divide both sides by ln(2)
a = 0/ln(2)
or
a = 0

=====
So if you had
=power(2,a) = x
you could do the same thing
2^a = 1
taking the natural log of both sides:
ln(2^a) = ln(x)
the left hand side becomes: a*ln(2)
so
a*ln(2) = ln(x)
divide both sides by ln(2)
a = ln(x)/ln(2)



Eric wrote:

Power(2,a) = 1,
Does anyone have any suggestions on how to determine the value of a?
Thank for any suggestions
Eric


--

Dave Peterson

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