Ask Singapore Homework?

Upload a photo of a Singapore homework and someone will email you the solution for free.



Question

secondary 4 | A Maths
One Answer Below

Anyone can contribute an answer, even non-tutors.

Answer This Question
There's a feeling
There's A Feeling

secondary 4 chevron_right A Maths chevron_right Singapore

How to do (ii)? Tks!

Date Posted: 4 years ago
Views: 200

See 1 Answer

done {{ upvoteCount }} Upvotes
clear {{ downvoteCount * -1 }} Downvotes
Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
1st
To get our R cos (theta - alpha), we must first position our function as a cos theta + b sin theta, where a and b are positive numbers.

Then, R = square root of (a^2 + b^2) like Pythagoras theorem.

Alpha is taninv of (b/a), where alpha is an acute angle.

For maximum value, we set cos (theta + alpha) to 1, because for any cosine function, -1 <= cos (...) <= 1.