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Calculus Honors Study Guide

Unit 5 · Core unit

Applications of Integration

The graded skill is the setup, not the antiderivative. Almost every lost mark here comes from the diagram, the slice, or the choice of variable.

What a strong answer looks like

A strong answer shows the representative slice before the integral: its dimensions, which curve is which, and which variable it is measured in.

Chapter introduction

Understand the idea before memorizing the rule

The graded skill is the setup, not the antiderivative. Almost every lost mark here comes from the diagram, the slice, or the choice of variable.

In Calculus Honors, success means moving among words, symbols, tables, and graphs while preserving the meaning of each quantity. Use the lessons below as connected notes: explain the concept, carry out the procedure, test the result, and interpret it in context.

Detailed study notes

Core lessons, reasoning, and common errors

1

Lesson 1

Area Between Curves

Concept explanation

The integrand is the vertical distance between the curves, upper minus lower, and the interval runs between their intersections.

How to apply it

Sketch first, find the intersections, and split the integral wherever the curves swap order.

Common mistake

Subtracting in the wrong order, or integrating across a crossing point without splitting.

Guided study move

Find an area where the curves cross inside the interval, so the integral must be split.

2

Lesson 2

Volumes of Revolution

Concept explanation

Disks and washers stack cross-sections perpendicular to the axis; shells wrap cylinders around it. The washer subtracts squares of radii, not the square of a difference.

How to apply it

Draw the slice, decide whether it is perpendicular or parallel to the axis, and write its area or volume before integrating.

Common mistake

Squaring the gap between two curves instead of subtracting their squares.

Guided study move

Set up the same solid by both washers and shells and confirm the two integrals agree.

3

Lesson 3

Average Value and Accumulation in Context

Concept explanation

The average value divides accumulated total by interval width. Integrating a rate gives net change, and integrating its absolute value gives total amount.

How to apply it

Check units at every step: a rate times a duration must leave the quantity being accumulated.

Common mistake

Reporting displacement when total distance was asked for.

Guided study move

Compute displacement and total distance for the same velocity function and explain the difference.

Formula and visual reference

Connect the symbols to the picture

Chapter synthesis

Ideas to connect

  • Sketching before setting up
  • Subtracting squares rather than squaring differences
  • Checking units on the result

Modeling lab

Transfer the chapter to a new setting

A region bounded by two curves is revolved about a line that is not an axis. Set up the integral, stating each radius as a distance from the line.

Mastery checklist

  • Set up an area integral requiring a split.
  • Set up a washer integral with correct radii.
  • Compute an average value.
  • Distinguish displacement from total distance.

Check yourself

  • When is it easier to integrate with respect to y?
  • Why is the washer integrand not the square of the difference?

Modeling drill

A region bounded by two curves is revolved about a line that is not an axis. Set up the integral, stating each radius as a distance from the line.

Area between curvesDisk methodWasher methodCylindrical shellsAverage valueDisplacementTotal distance