Resposta:

52571

Explicação passo a passo:

7×{7+8×[(4+8)×(√81×9)-42]+64}-3×2

7×{7+8×[(12)×(9×9)-42]+64}-6

7×{7+8×[(12)×(81)-42]+64}-6

7×{7+8×[(972)-42]+64}-6

7×{7+8×[930]+64}-6

7×{7+7440+64}-6

7×{7447+64}-6

7×{7511}-6

52577 - 6

52571

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