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SAI International School
                                                     CLASS - IX

               Mathematics
               CHAPTER-2:  ZERO OF A POLYNOMIALSLesson Notes-2


               Sub Topic :

               Zero of a Polynomial:
               It is the value of the variable for which the value of the polynomial will be equal to
               zero.
               If p(x) is a polynomial then the number ‘a’ will be the zero of the polynomial with p(a)
               = 0. We can find the zero of the polynomial by equating it to zero.
               For a polynomial  P(x), if P(a) =0, then a is called as the Zero of the polynomial.
               Example: 1

               Given polynomial is p(x) = x - 4

               To find the zero of the polynomial we will equate it to zero.

               x - 4 = 0

               x = 4
               p(4) = x – 4 = 4 – 4 = 0

               This shows that if we place 4 in place of x, we got the value of the polynomial as
               zero.  So  4  is the  zero  of  this polynomial.  And  also  we  are  getting  the  value  4  by
               equating the polynomial by 0.

               So 4 is the zero of the polynomial or root of the polynomial.

               Example ;  2
                     2
               Let X =4 so X= 2 and X= -2 are the zeroes of the polynomial
               VERIFICATION

                                     2
                            2
               For X=2 , X  – 4 = 2 - 4 =0 (Verified)
                             2
                                        2
               For X= -2 , X  – 4 = (-2) - 4 =0 (Verified)
               HOW TO FIND ZERO OF A POLYNOMIAL

               Consider the polynomial = 0
               P(X)=0

                                           Zero of a linear polynomial of one variable

               Let   P(X) = a x + b , where a is not zero


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