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Do you want to add up a list of numbers, convert from miles to kilometers, or evaluate some other mathematical expression? Instead of using a piece of paper, your calculator, or a computer math software program, you can solve mathematical problems with Google's built-in calculator function.

Simply enter the expression you'd like evaluated in Google's web search box and hit the ENTER key or click the "Google Search" button.

 Example:
The calculator can evaluate mathematical expressions involving:
Basic Arithmetic
Compute expressions containing standard mathematical symbols. The following table lists operators that come between the two numbers on which they operate, e.g., to multiply 2 times 3, use 2 * 3.

 Operator Function Example + Addition [ 15.99 + 32.50 + 13.25 ] - Subtraction [ 79 - 18 - 19 ] * Multiplication [ 2 * 3 * 7 ] / Division [ 378 / 9 ] ^ or ** Exponentiation (raise to a power of) [ 4^10 ] or [ 4**10 ] % of Percent [ 15% of 93.45 ] mod or % modulo (the remainder after division) [ 15 mod 9 ] or [ 15 % 9 ] the nth root of calculates the nth root [ 4th root of 16 ] [ cube root of 109 ] [ square root of 42 ] or [ sqrt(42) ]

Note: To do multiplication, you must include the * symbol; [ 3 * 4 ] will be calculated, 3 4 or 3 x 4 won't.

Compute results involving trigonometric, logorithmic and exponential functions as well as factorial and probability calculations

 Operator Function Example sin, cos, tan, sec, csc, cot, etc. Trigonometric functions (arguments are assumed to be in radians) [ cos(45) ] [ cosine(45) ] arcsin, arccos, arctan, arccsc, etc. Inverse trigonometric functions [ arccos(.5) ] sinh, cosh, tanh, csch, arsinh, arccsch, etc. Hyperbolic trigonometric functions [ cosh(6) ] ln Logarithm base e [ ln(16) ] log Logarithm base 10 [ log(16) ] lg Logarithm base 2 [ lg(16) ] exp Exponential function [ exp(16) ] ! Factorial [ 5! ] choose x choose y calculates the number of ways of choosing a set of y elements from a set of x distinct elements [ 5 choose 3 ]

Units of Measure and Conversions
Compute expressions involving different units. By default, units are converted to and results expressed in meter-kilogram-second (mks) units. Many units have both long and short names. Use whichever name you prefer.

 Type of Units Examples Mass kilogram or kg, grams or g, grains, pounds or lbs, carats, stones, tons, tonnes, etc. Length meters or m, miles, feet, Angstroms, cubits, furlongs, etc. Volume gallons, liters or l, bushels, teaspoons, pints, etc. Area square kilometers, acres, hectares, etc. Time days, seconds or s, centuries, sidereal years, fortnights, etc. Electricity volts, amps, ohms, henrys, etc. Energy Calories, British thermal units (BTU), joules, ergs, foot-pounds, etc. Power watt, kilowatts, horsepower or hp, etc. Information bits, bytes, kbytes, etc. Quantity dozen, baker's dozen, percent, gross, great gross, score, etc. Numbering systems decimal, hexadecimal or hex, octal, binary, roman numerals, etc. Prefix hexadecimal numbers with 0x, octal numbers with 0o and binary numbers with 0b. For example: 0x7f + 0b10010101.

Here are calculations that involve units.

[ 2 meters + 5 feet ]

Convert from one set of units to another by using the notation, x units in y units.

[ three quarters of a cup in teaspoons ]
[ 98.6 degrees Fahrenheit in degrees Celsius ]
[ 130 lbs in kg ]
[ 130 lbs in stones ]
[ 65 mph in kph ] or [ 65 mph in km/h ]

Warning: When your query includes "Calories" with a capital "C," Google returns kilocalories called "calories" by nutritionists.

[ 160 pounds * 4000 feet in Calories ]

Convert from one numbering system to another.

[ 1500 in hex ] or [ 1500 in hexadecimal ]
[ 64 in binary ]
[ MMIV in decimal ]

Mathematical and Physical Constants
The following table lists just a few of the commonly used mathematical constants known to the calculator function.

 Name and description Example base of the natural system of logarithms [ e ] pi, the ratio of the circumference to the diameter of a circle [ pi/6 ] imaginary number, i, which represents one of the two square roots of -1 [ i^2 ] Euler's constant, gamma [ e^gamma ]

And here are just a few of the many commonly used physical constants known to the calculator function.

 Long Name Shorthand Notation Click the Link for the Approximate Value atomic mass units amu or u [ u ] or [ atomic mass units ] Astronomical Unit au [ au ] or [ astronomical unit ] Avogadro's number [ Avogadro's number ] Boltzmann constant k [ k ] or [ Boltzmann constant ] Faraday constant [ Faraday constant ] gravitational constant G [ G ] or [ gravitational constant ] magnetic flux quantum [ magnetic flux quantum ] mass of a proton [ mass of a proton ] mass of each planet and of the sun [ m_mars ], [ m_earth ], [ m_uranus ] [ m_sun ] molar gas constant [ molar gas constant ] permeability of free space [ permeability of free space ] Planck's constant h [ h ] or [ Planck's constant ] radius of each planet and of the sun [ r_earth ], [ r_pluto ] [ r_sun ] speed of light in a vacuum c [ c ] or [ speed of light ] speed of sound in air at sea level mach [ speed of sound ]

Here are some calculations using built-in constants.

[ 1 AU/c ]
[ 1.21 MW / 88 mph ]
[ (G * mass of earth) / (radius of earth ^ 2) ]

Parentheses can be used whenever they'll serve to make complicated expressions unambiguous, but also that sets of parentheses can be used within parentheses; don't use brackets for grouping.

The following are tips from Google's online help for the calculator, which can be found on the web at www.google.com/help/calculator.html.

You can force the calculator to try to evaluate an expression by putting an equals sign (=) after it. This works only if the expression is arithmetically computable. For example, 1-800-555-1234= will return a result, but 1/0= will not.

Parentheses can be used to enclose the parts of your expression that you want evaluated first. For example, (1+2)*3 causes the addition to happen before the multiplication.

Feel free to experiment with the calculator as not all of its capabilities are listed here.

If you want a visual interface to a fraction of the capabilities of Google's calculator, visit Soople's Calculator page, www.soople.com/index.php?sub=calculator.

Exercises

This problem set is designed to give you practice in using Google's new calculator function. For hints and answers to selected problems, see the Solutions page in the Appendix.

1. Convert 1 mile to meters.

2. Convert 1 kg (kilogram) to lbs (pounds).

3. Convert 0 degrees Kelvin to Fahrenheit or Celsius.

4. Compute the number of minutes in a 365-day year.

5. Which is larger pi^e or e^pi? The same relationship holds between x^e and e^x for all non-negative values of x except e. The exponential constant, e, is approximately 2.72 and the ratio of the circumference to the diameter of a circle, pi, is approximately 3.14.

6. How many lottery combinations are there if the winning combination consists of 5 distinct integers between 1 and 99, i.e., there are 99 balls in an urn and once one is selected, it isn't returned to the box.

7. Compute the probability of your winning the lottery if you buy 1,000 tickets each bearing five distinct independently randomly chosen integers between 1 and 99.