设全集是实数集R,A={x丨2x-7x+3≤0},B={x丨x+a<0}[1]当a=-4时,求A∩B和A∪B
设全集是实数集R,A={x丨2x-7x+3≤0},B={x丨x+a<0}[1]当a=-4时,求A∩B和A∪B
设全集是实数集R,A=[x/2x的平方-7x+3小于等于0],B-[x/x的平方+a小于0]当a=-4时.求A交B、;A
设全集是实数集R,A={x|2x2-7x+3≤0},B={x|x2-4<0},求A∩B和A∪B.
设全集是实数集R,A={x丨2x²-7x+3≤0},B={x丨x²+a
设全集U=R,A={x/2x的平方-7x+3≤0},B={x/x的平方+a<0} (1)a=-4时求A∩B、A∪B
设全集是实数集R,A={x|2x²-7x+3≤0},B={x|x²-a<0}.
设全集是实数R,A={x丨2x²-5x-3≤0},B={x丨x²+a
设全集是实数集R,A={x|1/2≤x≤3},B={x|x²+a<0}
设全集是实数集R,A={X|1/2≤X≤3},B={X|X2 a
设全集是实数集R,A={X|2x^2-7x+3≤0},B={X|y^2+a
设全集是实数集R,A={x丨x2-4x+3≤0},B={x丨x-a2
设全集是实数集R,A={x/x大于等于2分之1小于等于3},B={X/x的绝对值+a小于0},1.a =-2时,求A交B