Chapter 7: Differential equations Notes

Differential equations and their solutions, slope fields, separable differential equations, equations of the form dy/dx = g(y), logistic growth, and modelling real situations with differential equations.

Sections

  1. 7A Differential equations and their solutions Mastered

    What a differential equation is, its order, checking that a function is a solution, general and particular solutions, families of solution curves, and using initial conditions to find constants.

  2. 7B Slope fields Mastered

    Drawing and reading slope fields (direction fields) for first-order differential equations, sketching solution curves through a point, matching DEs to slope fields, and spotting constant solutions.

  3. 7C Separable differential equations Mastered

    Solving separable differential equations dy/dx = f(x)g(y) by separating the variables and integrating both sides, finding constant solutions first, handling absolute values, and using initial conditions.

  4. 7D Equations of the form dy/dx = g(y) and logistic equations Mastered

    Solving dy/dx = g(y) by taking reciprocals, exponential growth, the logistic equation dP/dt = kP(1 − P/K), its solution, carrying capacity, constant solutions, and where the growth is fastest.

  5. 7E Applications of differential equations Mastered

    Modelling with differential equations, including exponential growth and decay, motion with air resistance and terminal velocity, mixing problems, the spread of a rumour or disease with the logistic model, and interpreting solutions.

Formula sheet