How to
approach odd, intimidating, and grotesque calculus problems
Adapted from
G. Polya’s classic “How
to Solve It” (1945)
1. Understand the problem in your bones (feels
like lab work)
a. Read and re-read the problem.
b. Can you draw a picture or make a
rough sketch?
c. Can you write out the first few terms
of the series?
d. What exactly is the question asking? Do you believe it?
e. Can you break a complicated problem
down into smaller, easier problems?
f. For abstract problems, can you think
of a simple example to gain intuition?
2. Devise a plan – find a path to the
solution (feels like brainstorming)
a. What is the connection between the
data given and the unknown?
b. Have you seen the problem before?
c. Have you worked a similar problem?
d. Is there a useful theorem?
e. What are other problems with the same
unknown?
f. Suppose you think of a related
problem that you have solved before…
i.
Can
you use the result (like the convergence of a known series)?
ii.
Can
you use the same method (like a method of integration)?
g. Can you restate the problem? How many ways can you restate it?
h. Is there a slightly simpler problem that
you can solve? Do it!
i. Is there a more general problem that
you can solve? Do it!
j. Can you drop part of the conditions and
solve the easier problem? Does this
help?
k. Can you add more data to the problem
and then solve it? Does this help?
l. Have you used all the information
given?
m. Once you “see” the solution, find a
logical and coherent plan to explain your reasoning.
3. Carry out the plan (feels like accounting)
a. Write out each step carefully.
b. Check your work as you go, so
mistakes don’t propagate.
4. Reflect on your solution (feels like
philosophy)
a. Does your answer make sense?
b. Is there a fast way (like taking a
derivative) to check your answer?
c. Is your answer what you expected from
step 1?
d. Is there something deep or surprising
about your solution?
e. Bask in the glory.