A²+4a-5=0
a1+a2=-4 U a1*a2=-5⇒a1=-5 U a2=1
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(a+5)(a-1)/(a+5)-1/[(a-2)(a-1)]=0
(a-1)-1/(a-2)²(a-1)=0
a≠2;a≠1
(a-1)²(a-2)²-1=0
[(a-1)(a-2)-1]*[(a-1)(a-2)+1]=0
(a²-3a+2-1)(a²-3a+2+1)=0
(a²-3a+1)(a²-3a+3=0
a²-3a+1=0
D=9-4=5
a1=(3-√5)/2 U a2=(3+√5)/2
a²-3a+3=0
D=9-12=-3<0 нет решения<br>