Array formula entering

Whats the difference between:

=PRODUCT(1-$A1:F1)

and

{=PRODUCT(1-$A1:F1)} (array entered)

The results seem to differ, the above is interpreted as:

(1-A1)*(1-B2)*...*(1-F1) for both cases?

The former's result will vary depending on where you enter it. The latter is correct.

first 1 only does value in a1
array looks at all the values in a1:f1

An array formula must be entered by pressing

Ctrl-Shift-Enter

at the same time. Depending on the formula you have in the cell, the array-entered version will differ if there is a range of cells to be evaluated in the formula. If you just enter the formula with the Enter key, only the first cell of any array in the formula will be interpreted.

You may not see a difference, depending on what the formula does and how many cells it spans. For more info about array formulas and how they work, see

http://www.xtremevbtalk.com/showthread.php?t=296012

cheers

Strictly speaking:
If you enter the first one in column A you get: =PRODUCT(1-$A1)
in column B you get: =PRODUCT(1-$B1)
etc. to column F. Anywhere else you get #VALUE!.