#import "../src/lib.typ": equate

#set text(size: 14pt)
#set par(justify: true)
#set page(
  width: 11cm,
  height: 4cm,
  margin: 1em,
  background: pad(0.5pt, box(
    width: 100%,
    height: 100%,
    radius: 4pt,
    fill: white,
    stroke: white.darken(10%),
  )),
)

#show: equate.with(breakable: true, sub-numbering: true)
#set math.equation(numbering: "(1.1)")

The dot product of two vectors $arrow(a)$ and $arrow(b)$ can be
calculated as shown in @dot-product.

$
  angle.l a, b angle.r &= arrow(a) dot arrow(b) \
                       &= a_1 b_1 + a_2 b_2 + ... a_n b_n \
                       &= sum_(i=1)^n a_i b_i. #<sum>
$ <dot-product>

The sum notation in @sum is a useful way to express the dot
product of two vectors.
