
Using the fact that cos is 2π-periodic, we have

That is,
for any
and integer
.

We get 2 solutions in the interval [0, 2π] for
and
,

Answer:
The perimeter is approximately 19.
Step-by-step explanation:
Three of the sides are roughly four segments long and two are around three and a half.
4 + 4 + 4 + 3.5 + 3.5 = 19
No solution because you can’t even out both sides