Question

Решите пожалуйста 2 и 3

Answer 1

$25^{3n+1} : 5^{2n-8} = ((5)^{2}) ^{3n+1} : 5^{2n-8} = (5) ^{2(3n+1)} : 5^{2n-8} = \\ = (5) ^{6n+2} : 5^{2n-8} =(5) ^{(6n+2) - (2n-8)}=(5) ^{6n+2 - 2n+8}= (5) ^{4n+10}$
Ответ; А

$7\sqrt{7} - 8 x^{3} =( \sqrt{7}) ^{2}\sqrt{7}- (2)^{3} x^{3} = ( \sqrt{7}) ^{3}- (2x)^{3}= \\ =( \sqrt{7} - 2x)(( \sqrt{7}) ^{2}+ \sqrt{7}*2x+(2x)^{2}) = ( \sqrt{7} - 2x)(7+ 2\sqrt{7}*x+4x^{2})$
Ответ: С