Question

Question 2 (i)
Find the values of k for each of the following quadratic equations, so that they have two equal roots.
$\left(i\right)2x^2+kx+3=0$

Answer 1

$\left(i\right)2x^2+kx+3=0$
Comparing equation with $a{x}^2+bx+c=0$, we get
$a=2,b=kandc=3$
$Discriminant=b^2-4ac$
$=(k{)}^2-4(2\left)\right(3)$
$=k^2-24$
For equal roots,
Discriminant = 0
$k^2-24=0$
$k^2=24$
$k=\pm \sqrt{24}=\pm 2\sqrt{6}$