I accidentally entered a function on a calculatot

Look for a key marked LN. Use SHIFT LN to access the exponential function. To enter the negative exponent use the change sign key (-) followed by 7. Press EXE/= to get the result.

On this calculator the exponential function requires the argument be entered first. To calculate the exponential of a number, you enter the exponent (0.08) then press [2nd][LN].
For your calculation, you should calculate e^(0.08) then multiply the result by (5000x2=10000). The result should be 10 832.87068

If you want to raise a number to another, use the ^ key located just above the divide key.
For natural antilogarithm (exponentiation of e), use 2ND [e^x] (the shifted function of the LN key).
For common antilogarithm (exponentiation of 10), use 2ND [10^x] (the shifted function of the LOG key).
To enter a decimal exponent as part of a number, use 2ND [EE] (the shifted function of the comma key, located just above the 7 key.

The exponential function and the natural logarithm (LN) are inverse of one another. They share the same physical key. To calculate the natural log [LN] press the key marked LN and enter the number. Close the parenthesis) and press [=]
To calculate the exponential, use the key combination [SHIFT][LN] followed by the number.

Use the (-) key (far left column, above RCL) to enter the negative sign.

First of all the manual. Here is a link to the download page of all chapters.
To get the value of "e" the base of the natural logarithm you calculate the value of the exponential e^x function for x=1, in other words
value of "e"=e^(1)=2.718281828

To get the square you can use (e(^1))^2, but that is clumsy.
You can use the rule about exponential functions (e^a)*e^b)=e^(a+b)
Thus (e^1)*(e^1)=e^(1+1)=e^2

To access the exponential function press [SHIFT][LN]
and the square of "e" is obtained by pressing
[SHIFT][LN] 2 [ENTER]
The result is 7.389056099.

Hello,
There is no key dedicated to e, the base of natural logarithm, the same as there is for pi. However you can find it as the VALUE of the exponential function e^(x) for x=1. To obtain the VALUE of e you press [SHIFT] [ln] to access e^x, enter 1 and press [EXE].

Thus
[SHIFT][LN]1 [EXE] gives 2.718281828.

If you need that numerical VALUE often you may want to store it into a variable, say E. To do that
[SHIFT][LN]1 [-->] [APLHA] E [EXE]

From experience, I know that it is not the VALUE of e that you need but the symbol e to define the exponential function. If you press [SHIFT][LN] you get a syntax error. You can never see e in a multiplication, addition, or other arithmetic operation.

In this calculator, the e is first and foremost the symbol for the exponential function. If you need to draw the exponential function of X
you press [SHIFT][LN] X. Parentheses are not needed for simple arguments as this one, but if the exponent is a complicated expression parentheses are needed.
If you mean exponential of X you type [SHIFT][LN] [X,theta,T], but if you want exponential of (x-3z+ 0.5 y^2), you must enclose the argument (the object of the function) between parentheses
[SHIFT][LN] [ ( ] x-3*z+ 0.5*y [^]2 [ ) ] [EXE].

Hope it helps.

Press [2nd] [LOG] to display the menu for logs and exponential functions. Select [LN]. Enter the (positive) number, close the right parenthesis and press [ENTER].

Hello,
Yes it does. All scientific calculators do logs, power, roots, exponential, trigonometric functions. Most do also hyperbolic and inverse hyperbolic functions.
Hope it helps.

there is a nice tutorial on prenhall.com
this works for ti 83, 83+, 84, 84+ and 84+ silver