Sederhakanlah A. 3 akar 3 x akar 245 B. ( akar 2 + akar 5 )(akar 2 - akar 5) C. ( akar 7 + akar 12 ) pangkat 2

A.
[tex] = 3 \sqrt{3} \times \sqrt{245} \\ = 3 \sqrt{735} \\ = 3 \sqrt{49 \times 15} \\ = 21 \sqrt{15} [/tex]
B.
[tex] = ( \sqrt{2} + \sqrt{5} ) (\sqrt{2} - \sqrt{5} ) \\ = 2 - 2 \sqrt{5} + 2 \sqrt{5} - 5 \\ = 2 - 5 \\ = - 3[/tex]
C.
[tex] = ( \sqrt{7} + \sqrt{12} )^{2} \\ = ( \sqrt{7} + \sqrt{12} )( \sqrt{7} + \sqrt{12} ) \\ = 7 + 2 \sqrt{84} + 12 \\ = 19 + 4 \sqrt{21} [/tex]