How is trigonometry used in video games

Trigonometry is used a lot in video games to calculate the distance between things. For example, in a game like Skyrim the game will use trigonometry to calculate the distance between the player and his objective and display it on the map.
For example, if the player was standing on the ground and the objective was on top of a hill 5 metres from the player that is 3 metres tall, you can use trigonometry to work out the distance. It would be the square root of 3² + 5², which is 5.8m.
This is just a very simple example, trigonometry is used all the time in modern games along with other maths.