Q.For the equation \(5x^2+9x+3=0\) , if the roots are \(α\) and \(β\), then what is the value of \(\cfrac{1}{α}+\cfrac{1}{β}\) ? (a) 3 (b) -3 (c) \(\cfrac{1}{3}\) (d) -\(\cfrac{1}{3}\)
Answer: B
For the quadratic equation 5x\(^2\)+9x+3=0, if the roots are α and β
Therefore, \(α+β=-\cfrac{9}{5}\)
and \(αβ=\cfrac{3}{5}\)
∴ \(\cfrac{1}{α}+\cfrac{1}{β}\)=\(\cfrac{β+α}{αβ}\)=\(\cfrac{\cfrac{-9}{5}}{\cfrac{3}{5}}\)=\(\cfrac{-9}{5}×\cfrac{5}{3}\)=-3
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