See Boy Mow Chau's answer to Aaron's Secondary 4 E Maths Singapore question

Boy Mow Chau's answer to Aaron's Secondary 4 E Maths Singapore question.

2 Upvotes

0 Downvotes

Date Posted: 5 years ago

Comments 1 add a comment

Boy Mow Chau

5 years ago

for part (ii), can use either method (b) or (c).

if use method (c), and if the unknown angle is obtuse, cos-1() will still directly give the correct angle.