[tex]6 \sqrt{8 } - 4 \sqrt{32} + \sqrt{128} [/tex]

6√8 - 4√32 + √128
= 6√4×2 - 4√16×2 + √64×2
= 6×2√2 - 4×4√2 + 8√2
= 12√2 - 16√2 + 8√2
= 4√2

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