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                 \ 06-Jan-2025  Bharat Arora   Proof-7             Reader’s Sign _______________________ Date __________





                                                                  2
                                                           3
                Next, subtract this new polynomial –6a  – 12a         Now, divide the first term of new dividend
                                                       2
                                                                         2
                                                3
                from the original dividend –6a  + 18a  + 5a – 110.    30a  + 5a – 110 by the first term of the divisor
                Pull down the remaining terms to obtain a new         a + 2. We get the second term of the quotient,
                              2
                dividend 30a  + 5a – 110.                             i.e., 30a and repeat the same process.
                                                                                         2
                                 –6a 2                                               –6a   +  30a
                                                                                         3
                                                                                                 2
                          a + 2  –6a   + 18a  + 5a – 110                      a + 2  –6a   + 18a  +  5a – 110
                                            2
                                    3
                                                                                         3
                                    3
                                 –6a   – 12a 2                                       –6a   – 12a 2
                                 +    +                                              +     +
                                                                                                 2
                                            2
                                         30a  + 5a – 110                                      30a  +  5a – 110
                                                                                              30a  + 60a
                                                                                                 2
                                                                                           –      –
                                                                                                  – 55a – 110
                Again, divide the first term of the new dividend –55a –110 by the first term of the divisor a + 2. We
                get the third term of the quotient, i.e., –55 and repeat the above process.
                                    2
                                 –6a   +  30a –  55                 Since, we get the remainder zero. Thus, we can
                                    3
                                            2
                          a + 2  –6a   + 18a  +  5a – 110           say that
                                                                                2
                                                                         3
                                                                                                           2
                                    3
                                 –6a   – 12a 2                      (–6a  + 18a  + 5a – 110) ÷ (a + 2) = –6a  + 30a –55
                                                                                      2
                                 +    +                             \ Quotient = –6a  + 30a – 55 and remainder = 0.
                                            2
                                         30a  +  5a – 110
                                            2
                                         30a  + 60a
                                      –       –
                                              – 55a – 110
                                              – 55a – 110
                                              +     +
                                                    0
                                        3
                                                         2
                Example 18: Divide (x  – 16 + 21x – 8x ) by (x – 1) and find the quotient and remainder.
                                                       2
                                       3
                Solution: We have (x  – 16 + 21x – 8x ) ÷ (x – 1)
                                                                                                      3
                                                                                                            2
                First, arrange the dividend and the divisor in descending order of degree, i.e., x  – 8x + 21x – 16.
                Then, proceed as follows:
                                     x   –  7x  +  14
                                       2
                                             2
                            x – 1    x   – 8x   + 21x  –  16
                                       3
                                       3
                                     x   –  x 2                Multiplying (x – 1) by x 2
                                   –     +
                                             2
                                          – 7x   + 21x  –  16
                                             2
                                          – 7x   +  7x         Multiplying (x – 1) by (–7x)
                                         +     –
                                                  14x  –  16
                                                  14x  –  14   Multiplying (x – 1) by 14
                                               –      +

                                                     –2        (On subtracting)
                                    2
                Thus, quotient = x  – 7x + 14 and remainder = –2.

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