In this post from February a set of VBA trigonometric functions were presented, using the derivations given on the Microsoft Developer Network site:
Unfortunately two of the functions were wrong; the correct versions are shown below:
| Inverse Secant | Arcsec(X) = Atn(1 / Sqr(X * X – 1)) + Sgn((X) -1) * (2 * Atn(1)) |
| Inverse Cosecant | Arccosec(X) = Atn(1 / Sqr(X * X – 1)) + (Sgn(X) – 1) * (2 * Atn(1)) |
I have corrected the spreadsheet, which can be downloaded from: VBA Trig Functions
Does anyone know how I can notify Microsoft of the error?
Newton Excel Bach, not (just) an Excel Blog 
no guarantees, but i’ve used this in the past.
xlfiles@microsoft.com
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Hi Doug –
Apparently if you have login credentials (what used to be called Passport, but now it’s anyone’s guess), you can submit comments to the MSDN articles. I’ve done that just now.
I don’t know whether anyone monitors or moderates the comments. I’ll try to remember to check back in a month.
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Thanks Gary and Jon.
We’ll see if we get any response.
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I sent a message to xlfiles, and got a nice reply from Dave Gainer, who said he’d forward it to the right people, but it might take a few days.
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