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I am currently doing an online course,so I don't have a teacher to ask.

Current chapter was dealing with combining questions.

An example would be $\frac1x \sin(x)=y$, where we would draw individual graphs and then the combined one as well. I have looked on Google and cannot find any material for me to learn how to combine them graphically.

Example Question

This is one of the questions I am supposed to be able to do,and yet I do not even know where to start! I can find the answer online but I need to learn this stuff for university so that's not the point!

Do you guys know where I can find resources to learn this stuff? My material does not explain anything at all!

Thank You!

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What have you tried? –  chubakueno Aug 18 '13 at 0:48
What does the question about graphing have to do with problem 73? I don't see any graph in it. –  Ross Millikan Aug 18 '13 at 1:04

1 Answer 1

up vote 1 down vote accepted

If problem 73 is your real question, it leads you through it. Let $c$ be the rotation speed of the pedals in rpm, $g$ the gear ratio (dimensionless), and $d$ the diameter of the rear wheel in inches. The point of the gear ratio is that if the front gear has $49$ teeth and the rear gear has $14$ teeth, the rear wheel will turn $\frac {49}{14}=\frac 72=3.5$ times for every turn of the pedals. The rotation rate of the rear wheel is then $cg$. The speed of the bike is this times the circumference of the rear wheel. The units I have chosen give the speed in inches per minute, so you need to convert to km per hour.

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Thanks it makes sense now! –  LoadingCode Aug 18 '13 at 2:46

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