Q13 of 30 Page 36

What should be added to the polynomial (x2 – 5x + 4) so that 3 is a zero of the polynomial.

Let ‘a’ be added to polynomial x2 – 5x + 4 so that 3 becomes it zero


Hence the polynomial is x2 – 5x + 4 + a


Now as 3 has become zero after adding ‘a’ hence when we substitute x by 3 we will get 0


⇒ 32 – 5(3) + 4 + a = 0


⇒ 9 – 15 + 4 + a = 0


⇒ – 6 + 4 + a = 0


⇒ – 2 + a = 0


⇒ a = 2


Hence 2 should be added to x2 – 5x + 4 so that 3 becomes its zero


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