Question

Determine os valores das expressões
(2 √7 +5 √3). (2 √7- 5 √3)
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Answer 1

Oie, Td Bom?!

$= (2 \sqrt{7} + 5 \sqrt{3} ) \: . \: (2 \sqrt{7} - 5 \sqrt{7} )$

$= (2 \sqrt{7} ) {}^{2} - (5 \sqrt{3} ) {}^{2}$

$= 4 \: . \: 7 - 25 \: . \: 3$

$= 28 - 75$

$= - 47$

Att. Makaveli1996