已知函數(shù)f(x)=x3+klnx(k∈R),f'(x)為f(x)的導(dǎo)函數(shù).
(Ⅰ)當(dāng)k=6時(shí),
(i)求曲線y=f(x)在點(diǎn)(1,f(1))處的切線方程;
(ii)求函數(shù)g(x)=f(x)-f′(x)+9x的單調(diào)區(qū)間和極值;
(Ⅱ)當(dāng)k≥-3時(shí),求證:對(duì)任意的x1,x2∈[1,+∞),且x1>x2,有f′(x1)+f′(x2)2>f(x1)-f(x2)x1-x2.
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發(fā)布:2024/4/20 14:35:0組卷:234引用:2難度:0.2
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(Ⅰ)若函數(shù)f(x)在(0,+∞)上單調(diào)遞增,求實(shí)數(shù)a的取值范圍;
(Ⅱ)若函數(shù)f(x)有兩個(gè)極值點(diǎn)x1,x2(x1≠x2),證明:.x1?x2>e2發(fā)布:2024/12/29 13:30:1組卷:138引用:2難度:0.2
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