Integration by Parts
LIATE, the Tabular Method, and Cyclic Integrals — A TLDR Primer
Integration by parts shows up on almost every calculus exam — and it's the technique that trips students up the most. The formula looks simple enough, but knowing when to use it, how to pick the right pieces, and what to do when it loops back on itself is where students lose points.
This TLDR guide covers everything you need to handle integration by parts with confidence. You'll see exactly where the formula comes from (it's just the product rule in reverse), how to apply the LIATE rule so choosing *u* and *dv* becomes routine, and how to work through the one-pass examples that appear most often on tests. From there, the guide walks through repeated application and the tabular method — the shortcut that turns long polynomial-times-exponential problems into a clean grid. A dedicated section handles cyclic integrals like $e^x \sin x$, where integration by parts seems to go in circles until you solve for the answer algebraically. The final section applies everything to definite integrals and calls out the mistakes students make most often, so you don't lose easy points to boundary-term errors.
This is a calculus 2 help resource for college students as well as a focused ap calculus bc exam prep companion — short enough to read in one sitting, detailed enough to replace a full chapter of lecture notes. No filler, no padding: just the formula, the method, and enough worked examples to make it stick.
Grab it before your next exam.
- State the integration by parts formula and explain where it comes from.
- Use the LIATE rule to choose u and dv reliably.
- Apply integration by parts repeatedly, including tabular integration.
- Handle cyclic cases where the original integral reappears.
- Evaluate definite integrals using integration by parts.
- 1. Where the Formula Comes FromDerives the integration by parts formula from the product rule and shows what kinds of integrals it is built for.
- 2. Choosing u and dv: The LIATE RuleTeaches the standard heuristic for picking u and dv so the new integral is simpler than the original.
- 3. Worked Examples: One PassWalks through the canonical one-application examples step by step, including products of polynomials with exponentials, sines, and logarithms.
- 4. Repeated Integration by Parts and the Tabular MethodShows how to apply the formula multiple times and introduces the tabular shortcut for polynomial-times-easy-function integrals.
- 5. Cyclic Integrals and Solving for the AnswerHandles cases like e^x sin x where integration by parts loops back to the original integral, and you solve algebraically.
- 6. Definite Integrals and Common PitfallsApplies integration by parts to definite integrals, evaluates the boundary term carefully, and lists the mistakes students make most often.