Saral Shiksha

                                                Class 9 Number Systems Notes download   Class 9                               Number Systems                               Notes Number Systems 1. Number: A number is a mathematical object which is used in counting and measuring. 2. Number system: A number system defines a set of values used to represent a quantity. 3. Natural numbers: A set of counting numbers is called the natural numbers. N = {1,2, 3, 4, 5,...} These are infinite in number. Here first natural number is 1 whereas there is no last natural number. 4. Whole numbers: A set of natural numbers including zero is called the whole numbers. W = {0, 1, 2, 3, 4, 5,...} Note: All na...

                                                              Class 9 Polynomials notes download POLYNOMIALS  1.Expression: An expression which is the combination of constants and variables and are connected by   some or all the operations addition, subtraction, multiplication and division is known as an   algebraic expression.   Example: 7 + 9x – 2x 2 + 5 6 xy  2. Constant: Which has fixed numerical value.   Example: 7, -4, 3/4, etc.  3. Variable: A symbol which has no fixed numerical value is known as a variable. Example: 2x, 5x 2   4. Terms: These are the parts of an algebraic expression which are separated by operations, like   addition or subtraction are known as terms.   Example: In the expression 5x 3 + 9x 2 + 7x – 3, terms are 5x 3 , 9x 2 , 7x and -3  5. Polynomial: An a...