Three vehicles turn left and right

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The discussion revolves around calculating the possible turning combinations for three vehicles at an intersection. The original poster uses combinations to determine the number of ways vehicles can turn left or right, arriving at eight total possibilities. An alternative approach is suggested using the Binomial Theorem, where the expression (1+1)^3 is expanded to illustrate the same result. This method emphasizes the mathematical principle that applies to any number of vehicles. The conversation highlights different mathematical strategies to solve the same problem effectively.
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Homework Statement
consider an Experiment in which each of three vehicles taking a particular freeway exit turns left or right at the end of the exit ramp. The eight possible outcomes are posible. my question is that How to calculate 8 possible outcomes?
Relevant Equations
permutation p =nPr
combination C = nCr
I did combination like
3C2=3 here 3 means three vehicles. 2 means both turns left
3C2=3 here 3 means three vehicles. 2 means both turns right
3C3=1 3 means all are left.
3C3=1 3 means all are right.

My question is that is there another way that helps to get the answer?
 
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You could just do there are 2 ways for the first vehicle to turn * 2 ways for the second vehicle to turn * 2 ways for the third vehicle to turn = 8 possibilities
 
robax25 said:
I did combination like
3C2=3 here 3 means three vehicles. 2 means both turns left
3C2=3 here 3 means three vehicles. 2 means both turns right
3C3=1 3 means all are left.
3C3=1 3 means all are right.

My question is that is there another way that helps to get the answer?
You are really calculating (1+1)^3 by first expanding it as (1+1)(1+1)(1+1) = 1 + (3*1) + (3*1) + 1` = 8.
This will be valid for any number of cars, see Binomial Theorem Wikipedia
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Essentially I just have this problem that I'm stuck on, on a sheet about complex numbers: Show that, for ##|r|<1,## $$1+r\cos(x)+r^2\cos(2x)+r^3\cos(3x)...=\frac{1-r\cos(x)}{1-2r\cos(x)+r^2}$$ My first thought was to express it as a geometric series, where the real part of the sum of the series would be the series you see above: $$1+re^{ix}+r^2e^{2ix}+r^3e^{3ix}...$$ The sum of this series is just: $$\frac{(re^{ix})^n-1}{re^{ix} - 1}$$ I'm having some trouble trying to figure out what to...

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