分别解不等式X-(1/2)(X+1)≥1与(y-3)/2 -(4y+5)/4>-2,并比较X,Y的大小?
由x-(x+1)/2≧1,得2x-(x+1)=x-1≧2,故得x≧3;
由(y-3)/2-(4y+5)/4>-2,得2(y-3)-(4y+5)=-2y-11>-8,-2y>3,故yy.
分别解不等式X-(1/2)(X+1)≥1与(y-3)/2 -(4y+5)/4>-2,并比较X,Y的大小?
由x-(x+1)/2≧1,得2x-(x+1)=x-1≧2,故得x≧3;
由(y-3)/2-(4y+5)/4>-2,得2(y-3)-(4y+5)=-2y-11>-8,-2y>3,故yy.