Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 1 - No. 23)
A boat sails 10 km due north and then 8 km in a south-easterly direction. To determine the final position of the boat you will need to consider:
Pythagoras' theorem
The sine rule
Trigonometry and vector addition
Only the sine rule
Giải thích
You'll need trigonometry (to deal with the angles) and vector addition (to combine the directions and distances).