Vault Of Euclid

Today's setWednesday, 16 September 2026

10 problems across Calculus and Linear algebra.

62
Days
620
Problems served
1 core Differential equations Calculus
Solve the initial-value problem \(y'' - 3y' - 10y = 0, y(0) = 0, y'(0) = 7\).

Sign in to see the solution.

2 core Differential equations Calculus
An archaeologist investigating the site of an ancient village finds a burial ground where the amount of carbon-14 present in individual remains is between 42 and 44% of the amount present in live individuals. Estimate the age of the village and the length of time for which it survived.

Sign in to see the solution.

3 warmup Differential equations Calculus
Solve the Bernoulli equation $y' - y = xy^2$.

Sign in to see the solution.

4 warmup Differential equations Calculus
$$x^2y' = y^2 + xy - x^2, \quad y(1) = 2.$$ (2.4.10)

Sign in to see the solution.

5 core Multivariable calculus Calculus
Find \( \text{div } \mathbf{F} \) for \( \mathbf{F}(x, y, z) = \langle xy, 5 - z^2 y, x^2 + y^2 \rangle \).

Sign in to see the solution.

6 core Parametric equations and vector functions Calculus
Enclosed by $r=6 \sin \theta$

Sign in to see the solution.

7 warmup Parametric equations and vector functions Calculus
Area of a polar region Find the area of the circle defined by \( r = \cos \theta \). (Recall this circle has radius \( 1/2 \).)

Sign in to see the solution.

8 core Parametric equations and vector functions Calculus
Find a general solution of $y'' - y' - 6y = 2(\sin 4x + \cos 4x)$.

Sign in to see the solution.

9 core Parametric equations and vector functions Calculus
For the curve $x = 4t, y = 3t-2$, find the slope and concavity of the curve at $t=3$.

Sign in to see the solution.

10 hard Vector spaces Linear algebra
\(x^2 = y^2 + z^2\)

Sign in to see the solution.