My Math Forum Maths homework

 Elementary Math Fractions, Percentages, Word Problems, Equations, Inequations, Factorization, Expansion

September 6th, 2015, 12:52 AM   #1
Newbie

Joined: Sep 2015
From: australia

Posts: 9
Thanks: 2

Maths homework

Hi,
I can't get my head around this problem. Any help is appreciated.
Attached Images
 mathss.JPG (17.5 KB, 17 views)

Last edited by skipjack; September 6th, 2015 at 01:11 AM.

 September 6th, 2015, 01:08 AM #2 Senior Member   Joined: Sep 2015 From: 4th Dimension Posts: 146 Thanks: 13 Math Focus: Everything (a little bit) It's easy. I will give you hints. First one tells the cost for given amount. Second one, try to remember $\displaystyle f'$ is the rate of change. I hope you find it. Last edited by skipjack; September 6th, 2015 at 01:13 AM.
 September 6th, 2015, 01:17 AM #3 Global Moderator   Joined: Dec 2006 Posts: 21,018 Thanks: 2251 Presumably, $f'\!(v)$ denotes the rate of change of $f(v)\!$ with respect to $v$.
September 6th, 2015, 01:24 AM   #4
Senior Member

Joined: Sep 2015
From: 4th Dimension

Posts: 146
Thanks: 13

Math Focus: Everything (a little bit)
Quote:
 Originally Posted by skipjack Presumably, $f'\!(v)$ denotes the rate of change of $f(v)\!$ with respect to $v$.
I am not sure, but I feel it represents rate of change of cost when the amount is at 200 l

Last edited by skipjack; September 6th, 2015 at 08:25 AM.

 September 6th, 2015, 01:34 AM #5 Newbie   Joined: Sep 2015 From: australia Posts: 9 Thanks: 2 a) would be for 200 litres cost 4200$? b) I'm not getting the rates of change idea Last edited by skipjack; September 6th, 2015 at 08:28 AM. September 6th, 2015, 04:09 AM #6 Senior Member Joined: Dec 2012 From: Hong Kong Posts: 853 Thanks: 311 Math Focus: Stochastic processes, statistical inference, data mining, computational linguistics Quote:  Originally Posted by skitdemon a) would be for 200 litres cost 4200$?
Yep.

Quote:
 b) I'm not getting the rates of change idea
When you produce more and more chemical, the unit cost of the chemical will increase. f'(200) = 0.05 means that the cost increases at a rate of 0.05 when you are at your 200th litre of chemical.

If you plot the function on a graph, and draw a tangent at the point where x = 200, the slope of the tangent will be 0.05, which shows how fast the cost is increasing at that exact point.

Last edited by skipjack; September 6th, 2015 at 08:28 AM.

September 6th, 2015, 04:20 AM   #7
Senior Member

Joined: Sep 2015
From: 4th Dimension

Posts: 146
Thanks: 13

Math Focus: Everything (a little bit)
Quote:
 Originally Posted by 123qwerty Yep. When you produce more and more chemical, the unit cost of the chemical will increase. f'(200) = 0.05 means that the cost increases at a rate of 0.05 when you are at your 200th litre of chemical. If you plot the function on a graph, and draw a tangent at the point where x = 200, the slope of the tangent will be 0.05, which shows how fast the cost is increasing at that exact point.
That's what I was saying.

Last edited by skipjack; September 6th, 2015 at 08:27 AM.

 September 6th, 2015, 08:17 AM #8 Newbie   Joined: Sep 2015 From: australia Posts: 9 Thanks: 2 I get it now, thanks!

 Tags homework, maths

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post louisbish New Users 1 June 8th, 2014 02:55 PM eddiewoo New Users 0 September 3rd, 2013 01:32 PM bas Number Theory 3 March 22nd, 2011 10:26 AM andi7 Algebra 6 March 13th, 2009 10:55 AM sageia Algebra 3 September 4th, 2008 11:15 AM

 Contact - Home - Forums - Cryptocurrency Forum - Top