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University Differential Equations In the University Differential Equations bundle

University Differential Equations Differential Equations and Direction Fields — Unit Notes

Every definition and theorem this unit expects you to know, stated once each and written to be revised from: 10 definitions and 4 theorems, 6 worked examples, 3 diagrams, in 14 printable pages. This page lists what the notes cover. The notes themselves come with the University Differential Equations bundle.

Unit notes — in the bundle

14 pages 14 definitions & theorems 6 worked examples 35 key words 6 Try-it pairs, answered 14-row at-a-glance table 35-entry glossary Fill-in-the-blank guided twin 3 diagrams Letter size, print-ready

Not sold separately. The practice worksheet for this unit is free, with no email and no account.

Differential Equations and Direction Fields — what the notes cover

7 sections, in the order the unit is taught. Each entry below is the title of a definition or a theorem the notes state in full.

What you need

Also in this section: 1 note on method and common errors.

Order, linearity and classification

  • Definition — Order, and the two variables
  • Definition — Linear equation of order n

Also in this section: 1 worked example, 1 note on method and common errors.

Solutions, families and initial conditions

  • Definition — Solution on an interval
  • Definition — General solution, particular solution, initial value problem
  • Theorem — Interval of validity

Also in this section: 1 worked example, 1 note on method and common errors.

Direction fields, isoclines and solution curves

  • Definition — Direction field and solution curve
  • Definition — Isocline

Also in this section: 1 worked example, 1 note on method and common errors, 1 diagram.

Autonomous equations and the phase line

  • Definition — Autonomous equation and its equilibrium solutions
  • Definition — The three kinds of equilibrium
  • Theorem — What an autonomous equation forces

Also in this section: 1 worked example, 1 note on method and common errors, 1 diagram.

Existence and uniqueness for an initial value problem

  • Definition — Normal form
  • Theorem — Existence and uniqueness

Also in this section: 1 worked example, 1 note on method and common errors.

Euler's method

  • Definition — Euler's method
  • Theorem — Concavity fixes the direction of the error

Also in this section: 1 worked example, 1 note on method and common errors, 1 diagram.

Where the notes are

The notes are one of the documents in the University Differential Equations Solutions Bundle, beside the unit test, the challenge problems and every worked answer key. The Differential Equations and Direction Fields practice worksheet is free and stays free.

Best value for the whole year

Every University Differential Equations topic — the complete Solutions Bundle

One download, one payment, the whole program. For all 9 University Differential Equations units: the worksheet, the reference notes, the challenge set, the unit test and every answer key — these notes included.

9 units · 36 PDFs · 182 pages$24.99
  • Worked solutions, not answer lists — every step written out
  • Covers the whole year's program at this level
  • Less than the price of one hour of tutoring — for the entire year's solutions
Everything paid, in one file $24.99CAD · one payment University Differential Equations bundle — coming soon Not on sale yet

Practise it, then test yourself

Notes on their own do not make anything stick. This unit has a free, printable practice worksheet, and an end-of-unit test that comes with the bundle.

Differential Equations and Direction Fields practice worksheet   About the Differential Equations and Direction Fields unit test

← All 9 University Differential Equations unit notes

Free practice worksheet

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