$???解： (2)頂點(diǎn)坐標(biāo)為(\frac {m-1}{2}，\frac {(m+1)2}{4})???$
$???把x=\frac {m-1}{2}代入y= (x+1)2，???$
$???得y=\frac {(m+1)2}{4}???$
$???不論m為何值，該函數(shù)的圖像的頂點(diǎn)都在函數(shù)y= (x +1)2的圖像上???$
$???(3)設(shè)頂點(diǎn)縱坐標(biāo)為z ，???$
$???則z=\frac {(m+1)2}{4} ???$
$???當(dāng)m=-1時(shí)，z有最小值0???$
$???當(dāng)m=- 2時(shí)，z=\frac {1}{4}???$
$???當(dāng)m=3時(shí)， z= 4???$
$???所以當(dāng)-2≤m≤3時(shí)，0≤z≤4??$
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