Question

已知集合M={x|y=√(2-x²)},集合N={y|y=x²-1,x∈R},则M∩N等于

Answer 1

M={x|y=√(2-x²)}={x|-√2≤x≤√2}

N={y|y=x²-1,x∈R}={y|y≥-1}

故M∩N={x|-1≤x≤√2}