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You are not logged in. #1 20081121 22:34:25
PreUniversity Mathematics1. If find n. 2. If find n. 3. From 6 boys and 4 girls, 5 are to be selected for admission to a particular course. In how many ways can this this be done if there must be exactly 2 girls? 4. Find the number of diagonals in a polygon of a side. How many triangles can be made? 5. Find the number of arrangements in which 6 boys and 4 girls can be arranged in a line so that all the girls sit together and all the boys sit together. 6. A family of 4 brothers and 3 sisters are to be arranged for a photograph in one row. In how many ways can they be seated if all the sisters sit together. 7. If 6 times the number of permutations of n things taken 3 together is equal to 7 times the number of permutations of (n1) things choses 3 at a time, find n. 8. In an election, a voter may vote for any number of candidates not greater than the number to be chosen. There are 7 candidates and 4 members are chosen. In how many ways can a person vote? 9. Using Binomial theorem, find the value of . 10. Find the coefficient of in the expansion of . Character is who you are when no one is looking. #2 20090522 09:32:35
Re: PreUniversity MathematicsHi ganesh; n=8 #2 ignoring the trivial 0 and 1: n=5 #9 By the binomial theorem: If we say x=100 and y= 1 and we plug these into the RHS of the above identity. We get; #10 Last edited by bobbym (20090524 11:46:04) In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #3 20090817 06:20:09
Re: PreUniversity MathematicsHi ganesh #4 20090817 06:24:24
Re: PreUniversity MathematicsHi ganesh #5 20090817 06:27:44
Re: PreUniversity MathematicsHi ganesh #6 20090817 06:33:08
Re: PreUniversity MathematicsHi ganesh #7 20090817 06:39:06
Re: PreUniversity MathematicsHi ganesh #8 20090817 07:15:25
Re: PreUniversity MathematicsHi ganesh; Last edited by bobbym (20090817 07:20:33) In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. 