Răspuns
a) √7 ( √3 - 2√8 ) + 5√56 - √84 = 6√14 - √21
= √21 - 2√56 + 5√56 - 2√21 =
= 3√56 - √21 =
= 3 × 2√14 - √21 =
= 6√14 - √21
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√3 ( 2√2 - 3√3 ) - √2 ( 2√3 - 3√2 ) = 15
= 2√6 - 3√9 - 2√6 + 3√4 =
= 3 × 3 + 3 × 2 =
= 9 + 6 =
= 15
