<span>|x| + |y| = 2, xy = 1
x=1/y
!x!+!1/x!=2
!x!^2-2!x!+1=0
(!x!-1)^2=0
x=1
y=1
x=-1
y=-1
как то так - наверное - я так думаю</span>
[y=3-x
[y=2
3-X=2
-x=2-3
-x=-1
x=1
<span>(3х-1)*(х+2)-(х-2)*(4х-3)=
3x</span>²+6x-x-2)-(4x²-3x-8x+6)=
<span>-x</span>²+16x-8=
<span>-(0.5</span>²)+16*0.5-8=
<span>-0.25+8-8=-0.25
</span>