[tex]2\sqrt[]{6}-2\sqrt[]{24}t[/tex]
Substraction:
1. Find prime factors of 24
[tex]\sqrt[]{24}=\sqrt[]{2^2\cdot6}[/tex]
2. As 2 squared has a exact square root extract it from the radical:
[tex]\sqrt[]{24}=2\sqrt[]{6}[/tex]
Then, you have the next expression:
[tex]\begin{gathered} 2\sqrt[]{6}-2\sqrt[]{24}=2\sqrt[]{6}-2(2\sqrt[]{6}) \\ \\ =2\sqrt[]{6}-4\sqrt[]{6} \end{gathered}[/tex]
Substract similar terms (taking square root of 6 as a common factor):
[tex]\begin{gathered} =(2-4)\cdot\sqrt[]{6} \\ \\ =-2\sqrt[]{6} \end{gathered}[/tex]
