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Showing posts from October, 2018

### Dictionary Rank of a Word | Permutations & Combinations

PERMUTATIONS & COMBINATIONS Rank of the word or Dictionary order of the English words like COMPUTER, COLLEGE, SUCCESS, SOCCER, RAIN, FATHER, etc. Dictionary Rank of a Word Method of finding the Rank (Dictionary Order) of the word  “R A I N” Given word: R A I N Total letters = 4 Letters in alphabetical order: A, I, N, R No. of words formed starting with A = 3! = 6 No. of words formed starting with I = 3! = 6 No. of words formed starting with N = 3! = 6 After N there is R which is required R ----- Required A ---- Required I ---- Required N ---- Required RAIN ----- 1 word   RANK OF THE WORD “R A I N” A….. = 3! = 6 I……. = 3! = 6 N….. = 3! = 6 R…A…I…N = 1 word 6 6 6 1 TOTAL 19 Rank of “R A I N” is 19 Method of finding the Rank (Dictionary Order) of the word  “F A T H E R” Given word is :  "F A T H E R" In alphabetical order: A, E, F, H, R, T Words beginni

### Quadratic Equations Class 10 Chapter 4

Quadratic equation Chapter 4 Class 10 Basic concepts on Quadratic Equation class 10, chapter 4  Relationship between the Coefficients and Roots,  Nature of roots, Discriminant, Quadratic Formula, method of completing the square. Complete explanation of quadratic equations QUADRATIC EQUATION :-  An equation whose degree is 2 is called a quadratic equation. $General\; Quadratic\; Equation\; is:\; \; ax^{2}+bx+c=0$ Difference  between the quadratic equations and quadratic polynomials. Quadratic equations are very similar to the quadratic polynomials. But they are different from each other because of the following reasons. Quadratic Equations Quadratic Polynomials General Quadratic Equations is    ax 2  + bx + c = 0 General Quadratic Polynomial is  P(x) = ax 2  + bx + c Solutions of quadratic equations are called its roots. Solutions of quadratic polynomials are called its zeroes.

### DIVISIBILITY TEST- CBSE Mathematics

Divisibility test for 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 with examples and explanation DIVISIBILITY TEST- CBSE Mathematics Divisibility Test  :- This topic contains the divisibility test by 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 with examples for more understanding. Divisibility Test by 2:-   ·    If unit digit of a number is even ( 0, 2, 4, 6, 8) then that number is divisible by “2” ·     All even numbers are divisible by “2”. Example 1 :- ·   Let given number is    258694 ·   Unit digit    of    this    number is     “4”    it is even. Therefore 258694    is    also    divisible      by    “2” Example 2 :- ·    Let given number is    2586947 ·    Unit digit of this number is      “7”, it is odd. So    the number 2586947 is not    divisible by “2”. DIVISIBILITY TEST- CBSE Mathematics Divisibility Test by 3:- ·    If sum of the digits of a given number is    divisible by “3” then that number is also divisible    by “3”. Example 1 :- ·     Let given numb

### Limits and Continuity-cbse mathematics

Limits and Continuity   Basic concepts and formulas based on limit and continuity important for the students of classes 11 and 12. Important formulas of chapter 13 class 11 and important formulas necessary for the students of class 12 chapter 5 Introduction Limit and continuity is the introduction of calculus. Calculus is that branch of Mathematics which mainly deals with the study of change in the value of a function as the point in the domain changes.   Definition:  Suppose f is a real function on a subset of the real numbers and let c be a point in the domain of f. Then f is continuous at c if $\lim_{x\rightarrow c}f(x)=f(c)$ ALGEBRA OF LIMITS $Let \; f(x)\; and\; g(x)\; be\; two\; functions \; such\; that\; \lim_{x\rightarrow 0}\; f(x)\; and\; \lim_{x\rightarrow 0}\; g(x) \; exists$$1)\; \lim_{x\rightarrow a}\left [ f(x)+g(x) \right ]=\lim_{x\rightarrow a}\: f(x)+\lim_{x\rightarrow a}\: g(x)$\[2)\; \lim_{x\rightarrow a}