Luuk stumped his math teacher with one of my puzzles. Then his math teacher gave him a problem that Luuk suggested to me. If AAA + BBB + CCC = BAAC, what is the value of each digit? The digits are distinct and whole numbers from 1 to 9. Watch the video for…

use complex numbers: https://www.youtube.com/watch?v=OcXqF8l2crI

proof of angle sum formulas for sine and cosine,
sin(a+b)=sin(a)cos(b)+cos(a)sin(b),
cos(a+b)=cos(a)cos(b)-sin(a)sin(b),
triangle proof,
angle addition identity of sine,
angle addition…

How I make my thumbnails, requested, blackpenredpen, math for fun

angle additional formula: a*sin(x)+b*cos(x)=Acos(x+𝛼)
https://youtu.be/DY5J3Xn3SoM


blackpenredpen,
math for fun

In this video I explicitly calculate the volume of a ball of radius r in R^n. The method I’m presenting uses only multivariable calculus and the disk method from single-variable calculus, but we’ll also visit some other goodies like the Beta function and…