问题
填空题
已知集合M={y|y=2x,x∈R},N={y|y=-x2+2x+2,x∈R},则M∩N=______.
答案
集合M={y|y=2x,x∈R}={y|y>0},
N={y|y=-x2+2x+2,x∈R}={y|y=-(x-1)2+3,x∈R}={y|y≤3},
所以M∩N={y|y>01}∩={y|y≤3},
═{y|0<y≤3},
故答案为(0,3].
已知集合M={y|y=2x,x∈R},N={y|y=-x2+2x+2,x∈R},则M∩N=______.
集合M={y|y=2x,x∈R}={y|y>0},
N={y|y=-x2+2x+2,x∈R}={y|y=-(x-1)2+3,x∈R}={y|y≤3},
所以M∩N={y|y>01}∩={y|y≤3},
═{y|0<y≤3},
故答案为(0,3].