А)x²/(x²-9)=(12-x)/(x²-9)⇒
x²=12-x;⇒x²+x-12=0
x₁,₂=-1/2⁺₋√1/4+12=-1/2⁺₋7/2;
x₁=-1/2+7/2=-6/2=-3;
x₂=-1/2-7/2=-8/2=-4;
б)6/(x-2)+5/x=3⇒(6x+5(x-2))=3x(x-2)⇒6x+5x-10=3x²-6x;⇒
3x²-17x+10=0;
x₁,₂=(17⁺₋√(17²-4·3·10))/6=(17⁺₋13)/6;
x₁=(17+13)/6=30/6=5;
x₂=(17-13)/6=4/6=2/3;
A) 125^(1.5) · 25^(-3/4) = 5^(3 · 1.5) · 5^ (2 · (-3/4) =
= 5^(4.5) · 5^(-1.5) = 5^(4.5 - 1.5) = 5³ = 125
Б) 2^(1.25) · 16^(1/16) = 2^(1.25) · 2^(4 · 1/16) =
= 2^(1.25 + 0.25) = 2^1.5 = 2√2