Mathematics and WeBWorK
Best Practices
1. Start working on your homework early; you can then fix problems before an assignment is due.
2. Use the Preview button to see how WeBWorK has parsed your answer.
3. When you are having trouble, get help from a person (your teacher, a teaching
assistant, or a classmate).
The third suggestion is probably the most important. WeBWorK will show you which
problems you are having difficulty with. It is then up to you to get help with them. If
you have started early, you can still get the problems right.
Frequently Asked Questions
Q: I prefer to do my homework on paper.
A: So do we! WeBWorK does not require students to work out the problems at their
computer. We recommend that students print out the assignments and work out
the problems on paper. Then enter the answers into WeBWorK.
Q: It is frustrating to keep guessing at answers
A: No one expects students to repeatedly guess at their homework answers. If you are
having problems, consult a person who might be able to help, be it your teacher,
a teaching assistant, or a classmate.
Q: WeBWorK won’t accept my answer unless I enter it in a special form
A: WeBWorK uses standard mathematical notation as much as possible, and it accepts answers entered in many different forms, as long as they are correct. If you
have examples where this is not the case, bring it to the attention of your teacher,
so he or she can take it to the WeBWorK administrators.
Q: It would be better if a teacher graded my homework so I could see where I was
going wrong
A: It would be nice to have a teacher grade your homework problems and indicate
exactly where you went wrong. But, for classes that use WeBWorK, most paper homeworks could only be spot checked (i.e., a small percentage were marked
right/wrong by a grader).
You can get this sort of help when doing WeBWorK problems. When you are getting a problem wrong in WeBWorK, you should get help from a teaching assistant
or from your instructor. By bringing your work, they can help you find where you
went wrong. If you start your homework early, you can do this and still submit
the right answer before the due date. That way, you get help on the problems you
are getting wrong and can still get them right.
Basics
1. Exponents: x2 could be entered as x^2. You want to use the caret symbol for
that, Shift + 6 usually does the trick.
2. Be careful with complicated exponents:
(a) x^2/3 is interpreted as (x2 )/3 which is
x2
3
(b) x^(2/3) is interpreted as x2/3
(c) 2^3*5 is interpreted as 23 · 5 which is the same as (23 ) · 5
(d) 2^(3*5) is interpreted as 23·5
(e) 3x^2 is interpreted as 3 · x2 which is the same as 3 · (x2 )
(f) (3x)^2 is interpreted as (3x)2
(g) 3 + x^2 is interpreted as 3 + x2
(h) (3+x)^2 is interpreted as (3 + x)2
(i) -5^2 is interpreted as −52 which is the same as −(52 ) which equals −25
(j) (-5)^2 is interpreted as (−5)2 which equals 25
3. Roots:
√
(a) x could be entered as sqrt(x)
√
(b) 5 x − 1 could be entered as (x-1)^(1/5), and similarly for all other higher
degree roots.
4. Fractions: be careful to put complicated numerators and denominators in parenthesis:
3
−1
x
x+3
−1
(b) (x+3)/x-1 is interpreted as
x
3
(c) x+3/(x-1) is interpreted as x +
x−1
x+3
(d) (x+3)/(x-1) is interpreted as
x−1
(a) x+3/x-1 is interpreted as x +
5. You can use the pipe symbol or abs function for absolute value.
usually does the trick.
Shift + \
(a) expression |x| could be entered as |x| or abs(x)
(b) expression |x − 3| could be entered as |x-3| or abs(x-3)
6. It is a very good idea to use the Preview Answers button to see how computer
interprets your input first, and only when you see that computer understood you,
submit your answer and get feedback by clicking Submit Answers button.
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Special Functions
1. Natural Exponent, ex , could be entered as exp(x).
2. Natural Logarithm, ln x, could be entered as ln(x).
3. WeBWorK always uses radians when calculating values of trigonometric functions. Trigonometric functions could be entered using their common names:
Math version
sin x
cos x
tan x
cot x
WeBWorK version
sin(x)
cos(x)
tan(x)
cot(x)
4. Inverse trigonometric functions are easier to enter with the arc- notation:
Math version
sin−1 x or arcsin x
cos−1 x or arccos x
tan−1 x or arctan x
WeBWorK version
arcsin(x)
arccos(x)
arctan(x)
5. Functions and exponents. You want to be careful when you have a combination
of a special function and multiplication or an exponent in WeBWorK:
(a) \sin 2x will be interpreted as [sin(2)] · x
(b) \sin (2x) will be interpreted as sin(2x)
(c) \sin x^2 will be interpreted as [sin(x)]2
(d) \sin (x^2) will be interpreted as sin(x2 )
Essentially, WeBWorK tries to evaluate the value of a function before doing any
other algebraic operations. That’s why \sin 2x gets interpreted by WeBWorK as
sine of 2 multiplied by x.
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