trig (1 Viewer)

[kazemagic]

Hai
so i was doing some revision and came across this question, and i dont really understand how do u do question b lol

thanks

 

[nightweaver066]

Always look at the previous part as its most likely used.

Rearrange part (a) as i notice how they look pretty similar and i'm going to let



Compare this to (b) and you notice how they're pretty similar. If you let and multiply everything by 2, you end up with the same equation as in (b).

So now you solve for theta, and you end up with one solution being 40 degrees, so one root being as

 

[kazemagic]

ohh thx weaver