# if alpha & beta are zeros of polynomial

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if alpha & beta are zeros of polynomial kx²+5x+2.such that 1/alpha²+1/beta² = 17/4.find the value of k

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α + ß = $\frac{-b}a=\frac{-5}k$

αß = $\frac ca=\frac 2k$

Now, $\frac1{\alpha^2} + \frac1{\beta^2}$ = $\frac{\alpha^2+\beta^2}{(\alpha\beta)^2}=\frac{(α+\beta)^2-2\alpha\beta}{(\alpha\beta)^2}$

$\cfrac{(\frac{-5}k)^2-4/k}{(\frac 2k)^2}$ = $\cfrac{\frac{25}{k^2}-\frac 4k}{\frac4{k^2}}$

= $\frac{25-4k}4=\frac{17}4$

⇒ 25 - 4k = 17

⇒ 4k = 25 - 17 = 8

⇒ k = 2