The number of polynomials having zeroes as -2 and 5 is:a)1b)2c)3d)More...
The polynomials x2-3x-10, 2x2-6x-20, (1/2)x2-(3/2)x-5, 3x2-9x-30, have zeroes as -2 and 5.
View all questions of this test
The number of polynomials having zeroes as -2 and 5 is:a)1b)2c)3d)More...
Understanding the Problem
The problem states that we need to find the number of polynomials that have -2 and 5 as their zeros. A polynomial can be expressed in terms of its roots.
Forming the Polynomial
The general form of a polynomial with given roots can be represented as:
- If p(x) is a polynomial with roots r1 and r2, then p(x) can be expressed as:
- p(x) = k(x + 2)(x - 5)
Here, -2 and 5 are the roots, and k is a non-zero constant that can take any real value.
Variability of the Polynomial
- The value of k can be any real number (positive, negative, or zero).
- Different values of k will yield different polynomials.
Examples of Polynomials
- If k = 1, then the polynomial is:
- p(x) = (x + 2)(x - 5) = x^2 - 3x - 10
- If k = -1, then:
- p(x) = -(x + 2)(x - 5) = -x^2 + 3x + 10
- If k = 2, then:
- p(x) = 2(x + 2)(x - 5) = 2x^2 - 6x - 20
Conclusion
Since k can take an infinite number of values, there are infinitely many polynomials that can be formed with -2 and 5 as zeros. Thus, the correct answer is:
- More than 3 (Option D).
The number of polynomials having zeroes as -2 and 5 is:a)1b)2c)3d)More...
Correct answer is D
as polynomial =K[x^2-(sum of zeroes)x+product of zeroes]
And we can put any value of K
which means there are numerous number of polynomial with defined zeroes.