• 2022-06-29
    函数[img=107x26]1803d350c790c81.png[/img]在点(1,-1,1)处方向导数最大值为( )
    A: [img=34x26]1803d350cfbaf8b.png[/img]
    B: [img=48x26]1803d350d7dfb3b.png[/img]
    C: [img=34x26]1803d350e045950.png[/img]
    D: [img=34x26]1803d350e841a8e.png[/img]