已知集合A={x丨x²-2x-3≤0},B={x丨x²-2mx+m²-4≤0}.若A交B=[0,3].求实数m的值求速回
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![已知集合A={x丨x²-2x-3≤0},B={x丨x²-2mx+m²-4≤0}.若A交B=[0,3].求实数m的值求速回](/uploads/image/z/3671515-19-5.jpg?t=%E5%B7%B2%E7%9F%A5%E9%9B%86%E5%90%88A%3D%7Bx%E4%B8%A8x%26%23178%3B-2x-3%E2%89%A40%7D%2CB%3D%7Bx%E4%B8%A8x%26%23178%3B-2mx%2Bm%26%23178%3B-4%E2%89%A40%7D.%E8%8B%A5A%E4%BA%A4B%3D%5B0%2C3%5D.%E6%B1%82%E5%AE%9E%E6%95%B0m%E7%9A%84%E5%80%BC%E6%B1%82%E9%80%9F%E5%9B%9E)
已知集合A={x丨x²-2x-3≤0},B={x丨x²-2mx+m²-4≤0}.若A交B=[0,3].求实数m的值求速回
已知集合A={x丨x²-2x-3≤0},B={x丨x²-2mx+m²-4≤0}.若A交B=[0,3].求实数m的值
求速回
已知集合A={x丨x²-2x-3≤0},B={x丨x²-2mx+m²-4≤0}.若A交B=[0,3].求实数m的值求速回
集合A:
x²-2x-3≤0
(x-1)²-4≤0
(x-1)²≤4
-2≤x-1≤2
-1≤x≤3
所以A={x|-1≤x≤3}
集合B:
x²-2mx+m²-4≤0
(x-m)²-4≤0
(x-m)²≤4
-2≤x-m≤2
-2+m≤x≤2+m
所以B={x|-2+m≤x≤2+m}
又因为
因为A交B=[0,3]
所以-2+m=0
所以m=2
已知集合A={x丨x²-2x-3≤0}={x|-1<=x<=3}
x²-2mx+m²-4≤0
( x-m-2)(x-m+2)<=0
B: m-2<=x<=m+2 若A交B=[0,3].
m-2=0 m=2