Today’s a typical Sunday where Miss Loi’s schedule is ultra-packed with joss sticks sessions (aka tuition). In any case, here’s a really standard question re-occurring in many exams to herald the end of your weekend:
A sector has radius r cm and angle θ radians. Given that its area is fixed, use calculus to find the approximate percentage change in its radius when its angle decreases by 2 %.
Should be easy enough for you this time 🙂 But still many students tend to be a little ‘lost’ when it comes to these kind of questions involving percentage change in angles.
You really need to know the right approach and equation to start off with. And do note the bolded part – don’t make any careless mistake!
