The solution set of the equation $pq{x^2} - {(p + q)^2}x + {(p + q)^2} = 0$ is
$\left\{ {\frac{p}{q},\,\frac{q}{p}} \right\}$
$\left\{ {pq,\,\frac{p}{q}} \right\}$
$\left\{ {\frac{q}{p},\,pq} \right\}$
$\left\{ {\frac{{p + q}}{p},\,\frac{{p + q}}{q}} \right\}$
If $x$ be real, the least value of ${x^2} - 6x + 10$ is
Let $x$ and $y$ be two $2-$digit numbers such that $y$ is obtained by reversing the digits of $x$. Suppose they also satisfy $x^2-y^2=m^2$ for some positive integer $m$. The value of $x+y+m$ is
The sum of all the roots of the equation $\left|x^2-8 x+15\right|-2 x+7=0$ is:
The number of real solutions of the equation $3\left(x^2+\frac{1}{x^2}\right)-2\left(x+\frac{1}{x}\right)+5=0$, is
The set of all $a \in R$ for which the equation $x | x -1|+| x +2|+a=0$ has exactly one real root is: