1) 4/2a-1+3-2a/1-2a=0
4/2a-1-3-2a/2a-1=04-3-2a=0
-2a=-1
a=1/2
2) x²/x-3+9/3-x
x²/x-3-9/x-3
x²-9=0
x=+-3
Преобразуем
(a²-5a+4)(2a+3)=2a³-10a²+8a+3a²-15a+12=2a³-7a²-7a+12
(2a²-a-10)(a-3)=2a³-a²-10a-6a²+3a+30=2a³-7a²-7a+30
2a³-7a²-7a+12-2a³+7a²+7a-30+3a²=3a²-18=0
a²=6 a=√6 a= -√6
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(a^2+4ab+4b^2)-9=(a+2b)^2-9=(a+2b-3)(a+2b+3)