if the zeroes of the cubic polynomials f(x) = kx cube - 8x square + 5 are α-β , α , α+β then find the value of k
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sum of zeroes = 8/k
a- b+ a+ a+ b= 8/k
3a = 8/k
a = 8/3k
as a is zero of it
f( a) = 0
k( 8/3k)^3 - 8 ( 8/3k)^2 +5 = 0
512/27 k^2 - 512 /9 k^2 +5 = 0
512/9 k^2 ( 1/3 - 1) = -5
((512/(9 k^2 ))( -2/3) = -5
512 × 2 / 9 × 3 × 5. = k^2
1024/135 = k^2
32^2/3^2 × 15 = k^2
k= 32/3 √15
= 32/3× 3.8
=32/11.4
= 2.8
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