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Help needed in a simple M1 vector question

Gold Phoenix

"Find the bearing of 2i + 3j?"

Diagram is drawn like this, right?

The solution says tanθ=2/3 which gives the answer 034°...but I can't seem to figure out why?

Thanks in advance

Reply 1

Ateo

Original post by Gold Phoenix

"Find the bearing of 2i + 3j?"

Diagram is drawn like this, right?

The solution says tanθ=2/3 which gives the answer 034°...but I can't seem to figure out why?

Thanks in advance

Because the bearing is calculated clockwise from north. Modify your triangle slightly to see how the angle could be obtained directly.

Reply 2

ZNU

Original post by Gold Phoenix

"Find the bearing of 2i + 3j?"

Diagram is drawn like this, right?

The solution says tanθ=2/3 which gives the answer 034°...but I can't seem to figure out why?

Thanks in advance

Since your trying to find the bearing, it is measured clockwise from North. So the angle you are trying to find is 90-θ. You can either find θ by arctan(3/2) and taking it away from 90 to get the bearing, or you could find the angle opposite θ in the triangle - it is the same angle you are looking for, Z angles. Doing it the second way, 2 becomes the opposite and 3 the adjacent, so it is arctan(2/3), which gives 034°