(a²-5)²-(2a+3)²=0
(a²-5-2a-3)(a²-5+2a+3)=0
(a²-2a-8)(a²+2a-2)=0
a²-2a-8=0
a1+a2=2 U a1*a2=-8
a1=-2 U a2=4
a²+2a-2=0
D=4+8=12
a3=(-2-2√3)/2=-1-√3
a2=-1+√3
А). -4x^5y^2*3xy^4= -12x^6y^6; б). (3x^2y^3)^2=9x^4y^6.
7/20-1/5х-х2=0
-х2-1/5х+7/20=0
D=0,04+1,4=1,44.
х1=0,2-1,44/2=0,2-1,2/2=-1/2=-0,5
х2=0,2+1,44/2=0,2+1,2/2=1,4/2=0,7.
Ответ:-0,5. 0,7.