• 2022-07-24
    若点[img=66x19]17e0a6804595ce9.jpg[/img]为曲线[img=54x19]17e0a6762c2a993.jpg[/img]的拐点,[img=28x19]17e0a67617718b6.jpg[/img]二阶可导,则[img=55x21]17e0c3ab8ce33ba.jpg[/img]