Ответ. x-y=4; (x+y)^2=4; 1). .x-y=4; x+y=2; 2*x=6; x=3; y=-1;
2). x-y=4; x+y=-2; 2*x=2; x=1; y=-3
(√a³ -a)/(a -2a^1/2 +1) =(a√a -a)/( (√a)² -2√a +1) =a(√a-1)/(√a -1)² =a/(√a-1) .
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не знаю
( 1/a^(√2 -1) ) ^(√2 +1) * a ^(√2+1) = 1/(a^(√2 -1)(√2+1)*a^(√2+1)=
1/(a^(2 -1) *a^(√2+1) = (1/a)*(a^√2) *a = a^√2.
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