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Could someone explain me how to calculate "exp"?

Basically I have to calculate intrinsic density for silicon at T = 200K $$n_i=(N_cN_v)^{1/2}exp(-\frac{E_G}{2E_T})[cm^{-3}]$$

$$\sqrt{N_c N_v}=1.3173\times10^{19}$$ $$E_G=1.14736$$ $$-\frac{E_G}{2E_T}=-33.35$$

I need to calculate \$exp(-33.35)\$

How can I calculate \$exp(x)\$?

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Nothing to do with electronic design. Question should be closed. – Leon Heller Apr 19 '12 at 22:28
yea I know, but I'm SO user and hoped I might get some help here, as this has nothing to do with programming :/ – Tensio Apr 19 '12 at 22:30
4  
Maybe try math.stackexchange.com – Kris Bahnsen Apr 19 '12 at 22:31
Um, calculator? Am I missing something? – AngryEE Apr 19 '12 at 22:34
yep, it's a function and if I calculate exp(x) using wolframalpha I get correct solution but what does that function stands for and how can I calculate it using calculator? – Tensio Apr 19 '12 at 22:41
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closed as off topic by Leon Heller, W5VO♦, Brian Carlton, Kortuk♦ Apr 20 '12 at 0:50

Questions on Electrical Engineering Stack Exchange are expected to relate to electronics design within the scope defined in the FAQ. Consider editing the question or leaving comments for improvement if you believe the question can be reworded to fit within the scope. Read more about closed questions here.

1 Answer

up vote 2 down vote accepted

\$exp(x)\$ can also be written as \$e^x\$. Most scientific/graphing calculators will have this as a function. The number e is a constant irrational number approximately equal to 2.71828183.

Note that Google will solve this if you use "exp(x)" as well as "e^x".

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yep it works, Thanks a lot :) – Tensio Apr 19 '12 at 22:45
On Windoze calculator it's inv ln – Federico Russo Apr 20 '12 at 14:19
@FedericoRusso So clever with the "Windoze". – W5VO♦ Apr 20 '12 at 15:10

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