Given the expression:
[tex]\frac{a}{4\sqrt{ab}}[/tex]You can rationalize the denominator by multiplying the numerator and the denominator by the square root in the denominator. Set up that:
[tex]=\frac{a}{4\sqrt{ab}}\cdot\frac{\sqrt{ab}}{\sqrt{ab}}[/tex]Remember the following Property for Radicals:
[tex](\sqrt{x})(\sqrt{x})=(\sqrt{x})^2=x[/tex]Then, you get:
[tex]=\frac{a\sqrt{ab}}{4(\sqrt{ab)^2}}[/tex][tex]=\frac{a\sqrt{ab}}{4ab}[/tex]Notice that there is an "a" in the numerator and in the numerator. Knowing that:
[tex]\frac{a}{a}=1[/tex]You get:
[tex]=\frac{\sqrt{ab}}{4b}[/tex]Hence, the answer is:
[tex]=\frac{\sqrt{ab}}{4b}[/tex]