RD Sharma - Mathematics

Book: RD Sharma - Mathematics

Chapter: 2. Polynomials

Subject: Maths - Class 10th

Q. No. 25 of CCE - Formative Assessment

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25

What should be subtracted to the polynomial x2 – 16x + 30, so that 15 is the zero of the resulting polynomial?

Given,


p(x) = x2 – 16x + 30


15 is the zero of the resulting polynomial,


So we get;


p(15) = (15)2 – 16 × 15 + 30


p(15) = 225 – 240 + 30


p(15) = 15


15 should be subtracted from the given polynomial to get 15 as the zero of the resulting polynomial.


We can also verify the answer;


By adding 2 to the given polynomial we get;


P(x) = x2 – 16x + 30 – 15


P(x) = x2 – 16x + 15


P(15) = 225 – 240 + 15


P(15) = 240 – 240


P(15) = 0


Hence proved that 15 is the right answer to get 15 as the zero of resulting polynomial.

Chapter Exercises

More Exercise Questions

8

The sum and product of the zeros of a quadratic polynomial are and — 3 respectively. What is the quadratic polynomial?