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Topic : PERMUTATION AND COMBINATION SHORTCUTS PART 1
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1)THE NO. OF PERMUTATIONS OF N THINGS TAKEN TOGETHER WHEN P ARE ALIKE OF ONE KIND, Q OF OTHER TYPE, R OF OTHER KIND AND REST OF ALL DIFFERENT IS . WE MAY CONTINUE IT FOR ANY NUMBER OF ITEMS.2)THE NO. OF PERMUTATIONS OF N DISSIMILAR THINGS, TAKEN ALL AT A TIME IS (N1)!3)THE NUMBER OF WAYS OF ARRANGING N DISTINCT OBJECTS ALONG A CIRCLE, WHEN CLOCKWISE AND ANTICLOCKWISE ARRANGEMENTS ARE CONSIDERED SAME IS 4)THE NUMBER OF NECKLACES FORMED WITH N BEADS OF
Topic : Permutations & Combinations  Made Easy
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Permutations and combinationsWhen we talk of permutations and combinations in everyday talk we often use the two terms interchangeably. In mathematics, however, the two each have very specific meanings, and this distinction often causes problems. In brief, the permutation of a number of objects is the number of different ways they can be ordered; i.e. which is first, second, third, etc. If you wish to choose some objects from a larger number of objects, the way you position the chosen objects is also important. With combinations, on the other hand, one does not consider the order in which objects were chosen or placed, just which objects were chosen. We could summar
Topic : Ramanujam !
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Ramanujam: By age 11, he had exhausted the mathematical knowledge of two college students who were lod
Topic : shortcut to find the rank of a given word
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Shortcut for finding the Rank having words repeated:Rank of AGAIN1 2 1 3 4A G A I N1st numbers r given to the letters in dictionary orderthen under each letter, write down the number of letters assigned with lesser number occuring towards the right of the letter under which v r writing. 1 2 1 3 4A G A I &n
Topic : HOW TO FIND ROOTS(IMAGINARY AND REAL )OF A CUBIC EQUATION?????
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HOW TO FIND ROOTS(IMAGINARY AND REAL )OF A CUBIC EQUATION?????
Topic : SET THEORY
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SET THEORYMULTIPLE CHOICE QUESTIONS1. If A = {1, 2, 5} and B = {3, 4, 5, 9}, then A ? B is equal to (a) {1, 2, 5, 9} (b) {1, 2, 3, 4, 9} (c) {1, 2, 3, 4, 5, 9} (d) none of these2. If A = {x: x = 3n, n ? 6, n ? N} and B = {x: x = 9n, n ? 4, n ? N}, then which of the following is false?(a) A U B = {3, 9, 27, 81,243, 729, 6561} (b) A ? B = {9, 81, 729, 6561} (c) AB = {3, 27,243} (d) A ? D = {3, 27, 243, 6561}3. If Y is the smallest set such that Y U {1, 2} = {1, 2, 3, 5, 9}, then Y is equal to (a) {1,2,3,5,9} (b) {3,5,9} (c) {1,2} (d) none of these4. If n (A) = 115, n (B) = 326, n (AB) = 47, then n (A U B) is equal to(a) 373 (b) 165 (c) 370 (d) none
Topic : cube root onemoreonly for perfect cubes
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write the list of cubes of 110 as follows1 12 83 274 645 1256 2167 3438 5129 729revise the last numbersknow pick a perfect cube to check:474552group it by 3 digits, 474 552 see the last digit, &nb
Topic : find the cube root easy technique
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General MethodThe divisor should not be too small. The smallness will giverise to big quotients with several digits. This will lead tocomplications.Another method is to multiply the given number by anothersmall number cubed and find the cube root. Final answer iscalculated by dividing the result by small numberExample 4: Find the cube root of 2We multiply 2 by 53The new Number becomes 2 x 125 = 250Find the cube root of 250 and divide the answer by 5 [since we multiplied the original number by 5Step 1250 : 0 0 0By inspection write down 6 and 34 as the first Q and R .Since 216 is the perfect cube close to 250 and thereminder from 250 is 34.Step 2250 : 0 0 0108 : : 34:
Topic : PLAY WITH GRAPHS
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PLAY WITH GRAPHS Please click like and comment the graph which you like.Try to find some relationship between graphs i.e y=x^2 and sin x and (sin x)^2 .Let your mind and brain blossomTell me the graphs that you want to display Graph for sin(x) 32302826242220181614121086422468101214161820222426283032 3.532.521.510.50.511.522.533.5 x: 10.5139131y: 0.88622658 Graph for cos(?x)
Topic : Modern Einstein Theory of Relativity
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Einstein's Theory of Relativity states that , "Agar ek ladke ke haath par kisi ladki ka haath ho to ek ghanta bhi ek minute ki tarah guzarta hai aur agar ek haath ek garam tave pe rakha ho to ek minute bhi ek ghanta ke barabar guzarta hai. "Best Explanation of Albert Einstein's Special Theory of Relativity rate if you like
Topic : Toughest Problems in The world(must have a look)
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Source Wikipedia.Don't forget to click like if you find it interestingMillennium Prize ProblemsFrom Wikipedia, the free encyclopedia This article is about the math prizes. For the technology prize, see Millennium Technology Prize.The seven problems are:The Millennium Prize Problems are seven problems in mathematics that were stated by theClay Mathematics Institute in 2000. As of March 2012, six of the problems remain unsolved. A correct solution to any of the problems results in a US$1,000,000 prize (sometimes called aMillennium Prize) being awarded by the institute. The Poincaré conjecture, the onl
Topic : can anyone explain dis..???
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if w is a cube root of unity.. we know dat 1+w+w^2 =0but if we apply A.M>G.M for 1,w,w^2we get thus we get 1+w+w^2 >3so y des two statements contradict????
Topic : Factorise!
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Rationalize the denominator of . With your answer in the form , and the fraction in lowest terms, what is ? Solution: We use the fact that . Let . Then we have:.Thus (note are interchangeable), and our answer is .
Topic : Prove
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Let be positive real numbers such that .Prove that: .. Solution: the above expression can be written like but using am,gm we know that so we have that now if we r able to prove that or we will be done but on simplifying this we have or or now here set and we r done...........
Topic : if a+b=1 x ab=1 y find a,b find x+y find xy
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find it plzzzif a+b=1xab=1yfind a,bfind x+yfind xy
Topic : a trick to calculate square of any number orally...
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u can calculate the square of any number dis trick which is based on d following formula ohkk....so d trick is...let say we have to find the square of 11(m taking a simple example first)..1.v find the nearest multiple of 10 to dat no.....like fr 11 it is 10...for 19 it is 20 and so on........2.now find the difference bw dat multiple of 10 and dat no...and add dat difference to d no of which we have to find d square...ie for 11....difference bw 10 nd 11 is 1..v add 1 to 11=12..3.now multiply d new no which v got by adding d difference(12) with dat nearest multiple of 10 which v found at first step..ie 12x10=1204.now add the square of difference to it...th
Topic : permutations and combinations problems.
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Topic : Practice Questions on Permutation & Combination
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how many times the digit 7 is written while writing the numbers from 1 to 1,00,00,000?
Topic : logs without tables !!!!!!!!!!!!
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Easiest Way to Find LOG OF ANY NUMBER WITHOUT USING TABLES This method has been found by a Mr. Satish sharma. This way is applicable only to the common logarithms (i.e. to base 10) First of all you will have to remember only 4 values. Log 2 = 0.3010 Log 3 = 0.4771 Log 5 = 0.6989 Log 7 = 0.8450 Let me take an example to illustrate the rest – Log 945 = Log(9.45 * 10^2) = Log(9.45) + Lo
Topic : ISAT online reg................
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ISAT 2012 online form started from 1 nov.2012IIST is Asia's 1st institute providing education in space science only from undergraduate program upto Ph.D programAfter completing B. tech u must work in ISRO at least for 5 years fees600/ for OBC(NCL) http://www.iist.ac.in/isat2012/ ISAT2012 www.iist.ac.in
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