Hey all,
I was just wondering if anyone could help me on how to approach rates questions correctly? Like what's your thought process when you see this kind of question. I find these the toughest differentiation involved questions because it needs you to pick out key words.
So can anyone help ?I am happy to reply of course and answer anything.
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Slenderman
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- 01-11-2015 17:51
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16Characters....
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- 01-11-2015 18:03
(Original post by Slenderman)
Hey all,
I was just wondering if anyone could help me on how to approach rates questions correctly? Like what's your thought process when you see this kind of question. I find these the toughest differentiation involved questions because it needs you to pick out key words.
So can anyone help ?I am happy to reply of course and answer anything.
-
Slenderman
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- 01-11-2015 18:11
(Original post by 16Characters....)
Got any example questions to go through from the textbook?
A spherical balloon of radius r cm has volume V cm^2 , where V = 4/3.pi.r^3. The balloon is inflated constantly at a rate of 10 cm^-3 s^-1. Find the rate of increase of r when r - 8. -
16Characters....
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- 01-11-2015 18:24
(Original post by Slenderman)
Don't use the textbook so much, it's just really old and dull. How about this exam paper example:
A spherical balloon of radius r cm has volume V cm^2 , where V = 4/3.pi.r^3. The balloon is inflated constantly at a rate of 10 cm^-3 s^-1. Find the rate of increase of r when r - 8., which is given by:
Note that you can findas one over
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Slenderman
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- 01-11-2015 18:32
Okay so dv/dr = 4pi.r^2
Sub 8 in and that gives me 256 pi.
so 1/256pi gives like 1.24...x10-3
I assume you then just multiply by 10 as that is dv/dt ??? -
16Characters....
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- 01-11-2015 18:36
(Original post by Slenderman)
Okay so dv/dr = 4pi.r^2
Sub 8 in and that gives me 256 pi.
so 1/256pi gives like 1.24...x10-3
I assume you then just multiply by 10 as that is dv/dt ???
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