Q1 of 108 Page 46

If one zero of the polynomial f(x) = 5x2 + 13x + k is reciprocal of the other than the value of k will be:

Let the first root be a.

So the second root as per the question is 1/a.


Product of zeroes = a × 1/a


= 1


When we compare the above quadratic equation with the generalized one we get,


ax2 + bx + c = 0


∴ a = 5, b = 13, c = k


Product of zeroes = c / a


k/5 = 1


Therefore k = 5


So the correct answer is C [5].

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