Mathematics · Physics

Differential Equations

247 Questions

Differential equations involve finding functions that relate variables to their rates of change. These questions cover first and second order equations and separation of variables. They are a core part of the mathematics syllabus for high level competitive exams.

First order separationSecond order linear equationsInitial value problemsPredator prey modelsCauchy Riemann equations

Differential Equations Questions

Multiple choice general knowledge math & puzzles
  1. xK where x does not exist

  2. Kx where K = +-e to the power of C

  3. Kx where K does not exist

  4. xK where x = +-e to the power of C

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Separating variables: dy/y = dx/x. Integrating: ln|y| = ln|x| + C. Exponentiating: y = Cx (where C is the constant of integration). The solution represents direct proportionality between y and x.

Multiple choice general knowledge
  1. Fixed-step discrete solver

  2. Fixed-step ODE type solver

  3. Variable-step discrete solver

  4. Variable-step ODE type solver

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Variable-step ODE solvers dynamically adjust step size to maintain accuracy while optimizing efficiency. They take smaller steps during fast-changing dynamics and larger steps during smooth behavior, making them ideal for continuous systems. Fixed-step solvers either waste computation with unnecessarily small steps or lose accuracy with steps that are too large.

Multiple choice
  1. e-2t u (t)

  2. e2t u (t)

  3. e-t u (t)

  4. et u (t)

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$\text{We have} \hspace{0.5cm} x(t) + 2x(t) = \delta(t) \\ \text{Taking Laplace transform both sides} \\ sX(s) - x(0) + 2X(s) = 1 \\ or \hspace{2cm} sX(s) + 2X(s) = 1 \\ X(s) = \frac{1}{s+2} \\ \text{Now taking inverse laplace transform we have} \\ x(t) = e^{2t}u(t)$