My friend needs help!

[manuels]

Helli math People! I Come to you because my friend is having problems solving some math stuff.. So if someone could be so kind and help it would be much appreciated.

I dont know anything math of this level so i just upload some screenshots. It might have something to do with physics and circuits and stuff.. Thank You.

 

[stapel]

Unfortunately, attempting to assist through a "translator" who doesn't speak the language is, sad to say, pretty much doomed to failure.

Instead, kindly please have your friend post with a clear statement of the exercises (I can't make out bits of your images), the friend's level of study (high school? university?), topic of study (trigonometry? electrical engineering?), and the friend's efforts so far, so we can see where things are bogging down.

Thank you!