Ask Singapore Homework?

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



Question

junior college 1 | H1 Maths
One Answer Below

Anyone can contribute an answer, even non-tutors.

Answer This Question
Shion
Shion
Date Posted: 7 years ago
Views: 625

See 1 Answer

done {{ upvoteCount }} Upvotes
clear {{ downvoteCount * -1 }} Downvotes
Muhd Ilman Fahmi
Muhd Ilman Fahmi's answer
42 answers (Tutor Details)
1st
Pardon the handwriting

You first start off with the area of a circle equation, A = pi × r^2, and then differentiate to get dA/dr

You are given rate of change of area, dA/dt, and using chain rule you can get dr/dt.

You can find the equation of r in terms of t or otherwise, in order to get the value of r at any given t, such like for part ii. (Bottom left)

With that, you can substitute any value of r to get the rate of change of radius over time.

Give it a try! Hope it helps