Question

If one root of the equation $4x^2+2x-1=0$ is $\alpha$, then other root is -

• A. $2\alpha$
• B. $4{\alpha }^3-3\alpha$
• C. $4{\alpha }^2+3\alpha$
• D. None of these

Answer 1

The correct option is A $2\alpha$

$4x^2+2x-1=0$

Given one root $=\alpha$

Let other root be $=\beta$

Product of roots $\alpha \beta =-\frac{1}{4}$

$\left[\frac{c}{a}\right]$

$\therefore \beta =-\frac{1}{4\alpha }$.