求I(a,b)=∫01(ax+b-x2)2dx的极小值点.
求I(a,b)=∫01(ax+b-x2)2dx的极小值点.
【正确答案】:I(a,b)=∫01[x4-2ax3+(a2-2b)x2+ 2abx+b2]dx=1/5-a/2+(a2-2b)/3+ab+b2=1/5-(a/2)+(a2-2b)/3+ ab+b2 令Ia=0,Ib=0,得:a=1,b=-(1/6) 即在(1,-(1/6))取得极小值.
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