# Leif Metcalf's Website

## Good things

Marco Pierre White’s cooking videos for Knorr Gabriel Verret Dehumidifiers

## Geometric proof of $\sin 2\theta = 2 \sin \theta \cos \theta$

To start with, let's draw the standard trigonometric unit circle diagram for the angles $\theta$ and $2\theta$:

## Advent of Code Day 1 — Mathematica

The first task of day 1 was to find a pair of numbers in a given list that sum to 2020:

Intersection[input, 2020 - input]