集合M={x|-1∵m包含于n∵N;x<-t/4∴-t/4≥2∴t≤-8x=-t/4∴-t/4≥2∴t≤-8很显然 t>=-8
∵m包含于n∵N;x<-t/4∴-t/4≥2∴t≤-8
x=-t/4∴-t/4≥2∴t≤-8
很显然 t>=-8