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How do this??can you give me a method or explain to me how to do this step by step PLEASE!!!!!!

sAint

- Thread starter saint_n
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- #1

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How do this??can you give me a method or explain to me how to do this step by step PLEASE!!!!!!

sAint

- #2

matt grime

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just to reiterate, the solution is to just count the ways, and that's something you can do if you don't presume it's beyond your capabilities.

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Gokul43201

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Sorrie havent replied for a while been kinda busy and sorrie again i thought there was a method because in our notes(which doesnt really help much) he has an example

Suppose choose 25 objects from 7 types of objects s.t. every type of object appears at least twice and at most 6 times..

he wrote some formula

[x^25](x^2 + x^3 +x^4 +x^5 +x^6)^7

so i thought x^25 is the 25 objects and the exponents 2 to 6 is the "at least twice and at most 6 times" and ^7 is the seven types of objects then he did some calculations which i understand and he got 6055.

I just got confused when the question i asked you before because i didnt know how to represent the way he did but im not sure since you were helping me out could my answer for the prev. question be

[x^27](1 + x + x^2 + ... + x^9)(1 + x + .. + x^27)^6

am i on the rite track????

Suppose choose 25 objects from 7 types of objects s.t. every type of object appears at least twice and at most 6 times..

he wrote some formula

[x^25](x^2 + x^3 +x^4 +x^5 +x^6)^7

so i thought x^25 is the 25 objects and the exponents 2 to 6 is the "at least twice and at most 6 times" and ^7 is the seven types of objects then he did some calculations which i understand and he got 6055.

I just got confused when the question i asked you before because i didnt know how to represent the way he did but im not sure since you were helping me out could my answer for the prev. question be

[x^27](1 + x + x^2 + ... + x^9)(1 + x + .. + x^27)^6

am i on the rite track????

Last edited:

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- #6

matt grime

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For instance, fix n, then the number of ways of choosing r objects from n (order unimportant) is the coefficient of x^r in the expansion of (1+x)^n

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ok,,so what i have now is correct???Just so i can get started...

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