Bentuk rasional dari 45 per akar 27 + akar 12

Kelas 9 Matematika
Bab Akar dan Pangkat

√27 = √9 . √3
√27 = 3√3

√12 = √4 . √3
√12 = 2√3

45/(√27 + √12)
= 45/(√27 + √12) . (√27 - √12)/(√27 - √12)
= 45 (√27 - √12) / (27 - 12)
= 45 (3√3 - 2√3) / 15
= 3√3

= {\frac{45}{ \sqrt{27} +\sqrt{12}}}

= {\frac{45}{ \sqrt{27} +\sqrt{12}}}

 = {\frac{ \sqrt{27}-\sqrt{12} }{ \sqrt{27}-\sqrt{12}}}

= {\frac{45\sqrt{27}-45\sqrt{12}}{15}}


= {3\sqrt{27}-3\sqrt{27}}


= {9\sqrt{3}-6\sqrt{3}}


= {3\sqrt{3}}