updates
How to read a contour plot?
I am taking machine learning, and I have seen a few contour plots in the course. It seems that I can't understand how to read this plot, I have tried...
Apr 20, 2026
Archive: Updates
updates
Explain with math why you should choose a "letter of the day" to guess on a MC test. [closed]
I have often heard it said that if you are taking a multiple choice test and you have a block of problems you cant get to you should choose a random lette...
Apr 20, 2026
updates
Inverse operation of xor
If $x = a$ xor $b$, given the values of $x$ and $a$ can we find $b$? In other words, which function can be applied on both sides in the equation to get th...
Apr 20, 2026
updates
Zero function is often a solution?
I wonder why do we get zero as the trivial solution many a times. For instace: The ordinary differential equation $y'=y(y-1)$ has $y=0$ and $y=1$ as ...
Apr 20, 2026
updates
How to find the center of a circle from a point on it, and a tangent line.
I am clearly not typing this in to search engines correctly, if it's possible. The teacher likes to ask trick questions, so it might actually not be ...
Apr 20, 2026
updates
How to make Pentagon made up of 5 isosceles trapezoids and 1 small pentagon
I'm helping a friend with a 3d design, and can't figure this out. I assumed it would be simple, but For whatever reason, I can't get the an...
Apr 20, 2026
updates
changing a complex number into $a+bi$ form
I saw a puzzle online today that read the following: "Write the complex number $\frac{z+2i}{iz+3i}$ in the form $a+bi$" I have tried multiplying by the co...
Apr 20, 2026
updates
Street Combinatorics - 6 by 7 grid
You go to school in a building located six blocks east and seven blocks north of your home. So, in walking to school each day you go thirteen blocks. All ...
Apr 20, 2026
updates
Area inside curve given by parametric equation
I have this parametric equation: $$ \text{C}: \qquad \vec r(t)=\left(\cos^3(t), \sin^3(t)\right), \qquad t \in [0, 2\pi] $$ How to find the area inside of...
Apr 20, 2026
updates
How to get rid of a power in one side of the equation?
I would say, take the root, but here the power is $-\alpha$. In my book about the level of optimal employment (L), they go from $\tag{1}((1-\alpha)/(1+tp)...
Apr 20, 2026
