9u^2-3=0

Solution for 9u^2-3=0 equation:

9u^2-3=0

a = 9; b = 0; c = -3;
Δ = b2-4ac
Δ = 02-4·9·(-3)
Δ = 108
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{108}=\sqrt{36*3}=\sqrt{36}*\sqrt{3}=6\sqrt{3}$
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-6\sqrt{3}}{2*9}=\frac{0-6\sqrt{3}}{18}
=-\frac{6\sqrt{3}}{18}
=-\frac{\sqrt{3}}{3}
$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+6\sqrt{3}}{2*9}=\frac{0+6\sqrt{3}}{18}
=\frac{6\sqrt{3}}{18}
=\frac{\sqrt{3}}{3}
$