A) 6 <2x<span><8
21</span><3y<span><24
27</span><2x+3y<span><32
b) 21</span><xy<span><32
84</span><4xy<span><128
</span><span>
</span>
1)Q(x)=x^4-8x³+x²-3x+x³+5x²=x^4-7x³+6x²-3x
2)D(x)=x^4-8x³+x²-3x-x³-5x²=x^4-9x³-4x²-3x
3)R(x)=x³+5x²-x^4+8x³-x²+3x=-x^4+9x³+4x²+3x
{5х+3у=1,4|*7
{-7х-10у=5|*5
{35х+21у=9,8
{-35х-50у=25
35х+21у+(-35х)+(-50у)=9,8+25
-29у=34,8|:(-29)
у=-1,2
5х+3*(-1,2)=1,4
5х-3,6=1,4
5х=1,4+3,6
5х=5|:5
х=1
{6х-у=4
{3х+5у=13|*(-2)
{6х-у=4
{-6х-10у=-26
6х-у+(-6х)+(-10у)=4+(-26)
-11у=-22|:(-11)
у=2
6х-у=4
6х-2=4
6х=4+2
6х=6|:6
х=1