trigonometry

Question

A man sets out to travel from A to c via b from a he travels a distance of 8 km on a bearing N 30 E to b from b he travels a further 6km due east

a. calculate how far c is

i north of A

ii east of a

b hence or otherwise calculate the distance ac correct to 1 decimal place

Answer 1

(a) (i) AP=8cos30=4√3=6.9km approx. This is distance north of A.

(a)(ii) PC=8sin30+6=4+6=10km. This is distance east of A.

(b) AC=√(AP²+PC²)=√(48+100)=√148=12.2km approx.

Comments

What did you use for drawing this figure?

---

GeoGebra. It’s a free app and it’s very good. Desmos is another very good free app with graphics. The developers are keen to offer a high class service for students and others in the field of mathematics. There’s a 3D Calculator app from GeoGebra which allows you not only to draw 3D graphs, but to view them stereoscopically using coloured 3D glasses. And it rotates 3D objects so that you can appreciate them from different points of view. I recommend all these.