If one root of the polynomial f (x) = 5x2 + 13x + k is reciprocal of the other, then the value of k is

Given;


f(x) = 5x2 + 13x + k


Let suppose roots are R and 1/R


Product of the roots = C/R = R×1/R


R×1/R = k/5


1 = k/5


So,


Here k = 5

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