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If α, β are the zeros of kx2 – 2x + 3k such that α + β = αβ then k = ?
We have,
p (x) = x2 – 2x + 3k
Now by comparing the given polynomial with ax2 + bx + c, we get:
a = 1, b = - 2 and c = 3k
In the question it is given that, are the roots of the given polynomial
∴ =
= -(
)
= 2 (i)
:
=
=
= 3k (ii)
Hence, by using (i) and (ii), we have
=
2 = 3k
k =