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[1] This scientific calculator is under permanent development, therefore, it may give wrong results at times. Always do sanity checks and if you are trying to calculate something important, verify your results with help of alternative tools like other calculators, hand calculations, etc. If you encounter unexpected behavior or wrong results, or if you want the calculator to expand its functionality, please send us an email at

[2] This calculator's administrator does not see or record expressions entered by the users. Neither does the administrator see or record the results of calculations. However, for quality improvement, the calculator tracks what operators and functions were used in the course of the day and whether the evaluations were successful or not. For example, expression "ln(123+456)" is recorded as "ln(xxx+xxx) [evaluation ok]". A comment "Hi Sylvia" is recorded as "aa aaaaaa [evaluation not ok]". These blanked-out records are not shared with anybody and are not used for any purpose other than improving functionality and performance of the calculator. These records are deleted from the server on daily basis. Still, users must never enter any personal or confidential data into the calculator.

[3] No calculator is truly universal. This calculator's functionality is aimed at common needs of students, scientists and engineers. The following table lists available operators, functions and constants:

+ 1+1=2  add
- 2-1=1  subtract
* 7*5=35  multiply
/ 35/7=5  divide
** 2**8=256  power
abs( ) abs(-1.3)=1.3  absolute value
acos( ) acos(0)=pi/2  arc cosine
ans deg(ans)  carry over result of previous calculation
asin( ) asin(1)=pi/2  arc sine
atan( ) atan(1)=pi/4  arc tangent
cos( ) cos(pi/3)=0.5  cosine
deg( ) deg(pi)=180  convert from radians to degrees
dice sqrt(dice)  random integer between 1 and 6
exp( ) exp(0)=1  exponential value
fact( ) fact(9)=362880  factorial
ln( ) ln(e)=1.0  natural logarithm
log( ) log(100)=2  logarithm to base 10
log( ,base) log(9, 3)=2  logarithm to the given base
mod( , ) mod(65, 7)=2  modulo
rad( ) rad(180)=pi  convert from degrees to radians
rand exp(rand)  random floating point number in the range [0.0, 1.0)
round( ) round(-pi*1000)= -3142.0  round to the nearest integer
round( , n) round( -pi*1000, 2)= -3100.0  round to n significant digits
round( , -n) round( -pi*1000, -2)= -3141.59  round to n decimal places
sin( ) sin(pi/6)=0.5  sine
sqrt( ) sqrt(9)=3  square root
tan( ) tan(pi/4)=1  tangent
[n] rad([2])  carry over result of n-th calculation
pi  π: ratio of circle's circumference to its diameter
(defined with many significant digits)
e  base of natural logarithm (defined with many significant digits)
g  standard gravity (9.80665 m/s**2)
R  ideal gas constant (8.3144598 J/(K*mol))
N  Avogadro's constant (6.022141E+23 per mol)

[4] Complex numbers are not supported at this time :-(

[5] If the expression you entered does not result in a real number (bad syntax, division by zero, square root of a negative number, etc.) the calculator will repeat the expression as if it was a comment. You can hit the Edit link and make corrections in the Batch edit window. Comments can be used to annotate expressions as shown in this example.

[6] If you click on an earlier valid expression, its result or sequence number, they get carried over into the input line.

[7] The intelligence and precision of this (and every) calculator are limited. Always do a sanity check. This example shows a wrong answer that this calculator gives for obvious reasons.

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