设集合M={XI2sinx>=1,0

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设集合M={XI2sinx>=1,0

设集合M={XI2sinx>=1,0
设集合M={XI2sinx>=1,0<=x<=TT},N={cosx<=1/2,0<=x<=TT},求M与N的交集

设集合M={XI2sinx>=1,0
由2sinx≥1,得:
sinx≥1/2,
又∵ 0≤x≤π,
∴ π/6≤x≤5π/6
即:M=={x I π/6≤x≤5π/6 },
由cosx≤1/2,0≤x≤π,
∴ π/3≤x≤π
即:N={x I π/3≤x≤π },
∴ M∩N={x I π/3≤x≤5π/6},

设全集U是实数集R,M={x|2x-4=0}包括M和N及其交集不好意思,我没听懂你的题意,能不

M={XIπ/6<=x<=5π/6},N={XIπ/3<=x<=π} MnN={XIπ/3<=x<=5π/6}