2.059
1)x²/y³+y/x=(x³+y³)/xy³
2)x/y²-1/y+1/x=(x²-xy+y²)/xy²
3)(x+y)(x²-xy+y²)/xy³*xy²/(x²-xy+y²)=(x+y)/y
4)(x+y)/y:[(x²-2xy+y²+4xy):(x+y)/x]=(x+y)/y:[(x+y)²*x/(x+y)]=(x+y)/y*1/x(x+y)=1/xy
2.060
1)3/(2x-y)-2/(2x-y)-1/(2x-5y)=[3(2x+y)(2x-5y)-2(2x+y)(2x-5y)-(4x²-y²)]/(4x²-y²)(2x-5y)=
=(12x²-30xy+6xy-15y²-8x²+20xy+4xy-10y²-4x²+y²)/(4x²-y²)(2x-5y)=-24y²/(4x²-y²)(2x-5y)
2)-24y²/(4x²-y²)(2x-5y)*(4x²-y²)/y²=-24
2,179
2a^4+a³+4a²+a+2 |2a³-a²+a-2
2a^4-a³+a²-2a a+1
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2a³+3a²+3a+2
2a³- a²+ a- 2
-------------------------
4a²+2a+4
(2a^4+a³+4a²+a+2)/(2a³-a²+a-2)=(a+1)+(4a²+2a+4)/(2a³-a²+a-2)