设集合M={(x,y)|x2+y2=1,x∈R,y∈R},N={(x,y)|x2-y=0,x∈R,y∈R},则集合M∩N是多少

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设集合M={(x,y)|x2+y2=1,x∈R,y∈R},N={(x,y)|x2-y=0,x∈R,y∈R},则集合M∩N是多少
设集合M={(x,y)|x2+y2=1,x∈R,y∈R},N={(x,y)|x2-y=0,x∈R,y∈R},则集合M∩N是多少

设集合M={(x,y)|x2+y2=1,x∈R,y∈R},N={(x,y)|x2-y=0,x∈R,y∈R},则集合M∩N是多少
联立 x²+y²=1
x² - y = 0 即 x² = y ≥ 0
消x :y²+y -1 = 0
y = (-1+√5)/2 或 y = (-1-√5)/2 (小于0,舍去)
x² = (-1+√5)/2
x = ± √[ (-1+√5)/2]
M∩N = { (√[ (-1+√5)/2] ,(-1+√5)/2),(- √[ (-1+√5)/2],(-1+√5)/2)}

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