Help w/simple excel log formula

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Hi to all,

I am having difficulty in getting the following formula to run in excel 2003:

10 x Log (base 10) (x/y^2)…..in this case “x” (column F) and “y” (column G) are found in columns on the same
worksheet/page, when I enter my formual for this it runs without error but I am getting the wrong result. A

Attached is a copy of the worksheet…. column “H” contains my results and column “K” contains the correct results.

Any assistance will be appreciated…

Marty

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=10*LOG10(F2/G2*G2)
is the same as
=10*LOG10(F2)

since dividing by G2 and then multiplying by G2 “cancels” it out.You either want:=10*LOG10(F2/G2^2)

or
=10*LOG10(F2/G2/G2)

or
=10*LOG10(F2/(G2*G2))

Steve

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I just noticed that the formula you list will not give the answers in K.

To ge teh answers you need:=LOG((F2/G2)^2)
which is equicvalent to:
=2*LOG(F2/G2)

Steve

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Hi Steve,

thanks for the assistance, yet I do not see how 10 x log(base 10) x (Y/S squared) becomes the above…clearly it works, yet why?

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It doesn’t. Either your formula or your “answer” is wrong.

To get the answers you indicate as “right”, the factor of 10 is not used and it is not x/y² it is (x/y)²

[Note in excel Log10(x) = Log(x,10) = Log(x), the log function defaults to base 10 if no base is indicated]

Steve

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my sentiments exactly, thatnks for the assistance Steve….

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