Note: You must always execute the following command first to get the Maple DE toolbox. Replace the colon by a semicolon and then press enter if you want to see all the commands that become available. Better yet, get Maple help on "DEtools".

QyQtSSV3aXRoRzYiNiNJKERFdG9vbHNHNiQlKnByb3RlY3RlZEdJKF9zeXNsaWJHRiUhIiI=

Next, define the differential equations. Here's three interesting systems:

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print(); # input placeholder

Time for a "phase plane" plot, replete with arrows, which also makes it a "direction field" for Exercise 6.1.23:

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Exercise 6.1.24:

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Exercise 6.1.25:

QyQtSSdERXBsb3RHNiI2KUklREUyNUdGJTckLUkieEdGJTYjSSJ0R0YlLUkieUdGJUYrL0YsOyIiISIiIi9GKjshIiYiIiYvRi5GNDcnNyQvLUYqNiNGMUYxLy1GLkY8RjI3JEY6L0Y+IiIjNyQvRjtGMi9GPkYxNyQvRjtGQUZENyRGQ0Y9L0knYXJyb3dzR0YlSSdtZWRpdW1HRiVGMg==

Exercise 6.1.26:

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