If α and β are the roots of the equation,

Question:

If $\alpha$ and $\beta$ are the roots of the equation, $7 x^{2}-3 x-2=0$, then the value of $\frac{\alpha}{1-\alpha^{2}}+\frac{\beta}{1-\beta^{2}}$ is equal to:

  1. $\frac{27}{16}$

  2. $\frac{1}{24}$

  3. $\frac{27}{32}$

  4. $\frac{3}{8}$


Correct Option: 1

Solution:

$7 x^{2}-3 x-2=0$

$\alpha+\beta=\frac{3}{7} \quad \alpha \beta=\frac{-2}{7}$

$\frac{\alpha}{1-\alpha^{2}}+\frac{\beta}{1-\beta^{2}}=\frac{\alpha+\beta-\alpha \beta(\alpha+\beta)}{1-\alpha^{2}-\beta^{2}+\alpha^{2} \beta^{2}}$

$=\frac{\frac{3}{7}+\frac{2}{7}\left(\frac{3}{7}\right)}{1-(\alpha+\beta)^{2}+2 \alpha \beta+\alpha^{2} \beta^{2}}=\frac{27}{16}$

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