no 18 dong dapet point 15

[tex]\displaystyle \sqrt{18-2\sqrt{32}}=\sqrt{16+2-2\sqrt{16\cdot2}}\\\sqrt{18-2\sqrt{32}}=\sqrt{16}-\sqrt{2}\\\boxed{\boxed{\sqrt{18-2\sqrt{32}}=4-\sqrt{2}}}[/tex]

Bab Bilangan Irrasional
Matematika SMP Kelas IX

√(18 - 2√32)
= √(16 + 2 - 2 √(16 . 2))
= √16 - √2
= 4 - √2

jawabannya A