12 per akar 7-2 adalah

[tex] = \frac{12}{ \sqrt{7} - 2 } \times \frac{ \sqrt{7} + 2}{ \sqrt{7} + 2} \\ \\ = \frac{12 \sqrt{7} + 24 }{7 - 4} \\ \\ = \frac{12 \sqrt{7} + 24}{3} \\ \\ = 4 \sqrt{7} + 8[/tex]