Question

If one root of the polynomial 4x^2 - 9x + 8k is reciprocal of the other,find the value of k+5


options are in the attached picture


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Answer 1

Given: The equation 4x^2 - 9x + 8k = 0

To find: the value of k+5

Solution:

• Let the roots be a and 1/a.

• Then, the sum of roots will be:

               a + 1/a = 9/4

• Product of roots will be:

               a(1/a) = 8k/4

               1 = 2k

               k = 1/2

• Now k + 5 will be:

               1/2 + 5 = 10 + 1 / 2 = 11/2

Answer:

           So the value of k + 5 is 11/2