The GM really wanted to rein them in before they went off on too much of a tangent.
Lest you think trigonometric functions are going way over the top, there is a canonical game rule that uses cube roots. GURPS Vehicles, the vehicle design, statistics, and action rules for GURPS contains a few formulae with cube roots in them for calculating the performance statistics of water craft.
Just imagine what Pete could get up to with that.
Commentary by memnarch (who has not seen the movie)
And she's walking and walking and walking and walking..... At least the view is nice.
I wonder what the lore idea was behind this island when the writers came up with this scene. There don't seem to be any living places on this island and, well, it's an island. In a setting where hover vehicles are cheaper/easier to maintain than wheeled ones. Maybe it's meant to be super mega old? Star Wars is literally "A Long Time Ago", so how does that get exaggerated but by going even further back?
Transcript
GM: The ancient hand-carved steps wend their way up the steep island.
Rey: Remember my Stamina training is based on 300 rounds of walking on level terrain.
Rey: Uphill should give a multiplier.
Allan: Hmm. One over the cosine of the slope?
Rey: I’m thinking squared. A 45° slope should be at least double credit.
Allan: Ah, no. One over cosine is infinite if you climb a ladder.
Rey: Shhh!!!
GM: You realise I am not putting trig functions into the game rules?