Hah! Good retort, Gerson!

(On the other hand, maybe 1993 isn't "old" in the sense of classic HP; the attention to detail in the product literature was slipping by then.)

The error I see in the algebraic expression is that 2*pi should have been parenthesized, so that the square root would be applied to both numbers.

This is an example of my basic objection to EOS calculators: The expression you see in the display (which is often cropped) just *doesn't match* the graphical expression on the paper. Therefore, it is difficult to ascertain whether the entered expression was correct, yet the user is expected to trust the final result returned by hitting "=".

The HP-48 Equation Writer helped to avert errors such as these, but it's kind of a chore to enter a graphical expression using the cursor arrows.

-- KS

*Edited: 13 Jan 2007, 3:26 p.m. *