This topic describes how to enter mathematical and scientific expressions for problems in your edX course.
For some math, science, and other problems, you must enter a numerical or math expression, such as a formula, into a response field. You enter your response as plain text, and the edX system then converts your text into numbers and symbols that appear below the response field.
Additionally, some edX courses offer a calculator tool that you can use while you work through the course. If the course has a calculator, the calculator appears as a small icon on all courseware pages.
To use the calculator, select the calculator icon. To close the calculator, select the X.
Both the calculator and the response fields in math problems accept a selection of characters that represent numbers, operators, constants, functions, and other mathematical concepts. You might recognize parts of this system if you have used math programs before.
The calculator includes an information page that shows an abbreviated version
of the information in this topic. To see the information page, select the
i icon next to the input field.
When you enter your plain text into the calculator or the response field, follow these guidelines.
m*c^2, and instead of
( )) to specify the order of operations and to make your expression as clear as possible. Use curved parentheses (
( )) only. Do not use brackets (
[ ]) or braces (
v_IN-v_OUT. Note, however, that subscripts cannot currently include operators or parentheses.
For more information about the types of characters you can use, see below.
The edX system accepts both constants and metric affixes. Be careful to distinguish between constants and metric affixes. Constants stand alone, while metric affixes must be combined with numbers.
c can be a constant representing the speed of light or a
metric affix meaning “centi”. When you use
c as a metric affix, don’t
include a space between
c and the number. When you use
c as a
constant, indicate multiplication explicitly. The following examples show the
0.02(2 multiplied by 0.01)
599584916.0(the speed of light multiplied by 2)
2,000,000(2 multiplied by 1,000,000)
2*M= 2 multiplied by the variable M
You can use the following types of numbers:
The largest number you can use is 1.7977e+308, which is the largest float possible in the Python programming language.
You can enter metric affixes or scientific notation to indicate very large or
very small numbers. For scientific notation, you can type either a caret (^) or
e followed by a number to indicate an exponent. You can use both
positive and negative exponents.
For example, to indicate
0.012, you can enter either of the following
-440,000, you can enter either of the following expressions:
The following table shows how to enter numbers with metric affixes, with
scientific notation, and with
|To enter this number||Use this metric affix||Use this scientific notation||Use this
|0.01||1c (centi)||10^-2||1e-2||1% (percent)|
When you use metric affixes or
e notation, make sure you do not
include spaces between the number and the metric affix or the
You can use several different constants in your mathematical expressions.
When you enter constants multiplied by a number, make sure to
indicate the multiplication explicitly. For example, enter
2*c instead of
-4*i instead of
||The speed of light in m/s (2.998^8)|
||Euler’s number (2.718...)|
||Gravity (9.80 m/s^2)|
||The square root of -1|
||The square root of -1|
||The Boltzmann constant (~1.38^-23 in Joules/Kelvin)|
||The ratio of a circle’s circumference to its diameter (3.14159...)|
||The fundamental charge (~1.602^-19 Coloumbs)|
||The positive difference between 0K and 0°C (273.15)|
To use any of the following Greek letters, type the name of the letter in the calculator or the response field.
epsilon is the lunate version, whereas
like a backward 3.
To use a function, type the letters that represent the function, and then
surround the expression in that function with parentheses. For example, to
represent the square root of
You can use the following functions.
factorial(3). You must use integers. For example, you can’t enter
||). For example,
1 || 2represents the resistance of a pair of parallel resistors (of resistance 1 and 2 ohms), evaluating to 2/3 (ohms).