[tex] \frac{4x}{\sqrt{9x+8}} [/tex]
to rationalise we multiply both numerator and denominator by [tex] \sqrt{9x+8} [/tex]
So we do
[tex] \frac{4x}{\sqrt{9x+8}} * \frac{\sqrt{9x+8}}{\sqrt{9x+8}} [/tex]
=[tex] \frac{4x(\sqrt{9x+8})}{9x+8} [/tex]
As it cannot be simplified anymore so this is the final answer
[tex] \frac{4x(\sqrt{9x+8})}{9x+8} [/tex]
