positive: DELETE Open File(打开文件) CTRL+O(字母) New Scene(新建场景) CTRL+N Save Fil e(存储文件) CTRL+S Hold(暂存) ALT+CTRL+H Fetch(恢复至最后一次暂存状态) ALT+CTRL+F Expert Mode(专家模式) CTRL+X Undo Scene Operation(撤消场景操作) CTRL+Z Redo Scene Operation(重做场景操作) CTRL+Y Smart Select(选择模式) 注:当选择按钮被激活后再按Q键为循环选择Fence Selection Region(围栏式选择区 域)方式。 Cycle Selection Method(循环选择选择方式) CTRL+F Move Mode(移动模式) RotateMode(旋转模式) SmartScale(缩放模式) ScaleCycle(循环缩放模式) CTRL+E Restrict X(限制X轴向) F5 Restrict Y(限制Y轴向) F6 Restrict 轴向)
negative: "由y=x³,在点P(1,1)处斜率为:<br>y′=3x,x=1时,斜率k=y′=3,<br>∴切线方程:y-1=3(x-1)<br>得:y=3x-2,<br>令y=0,x=2/3,A(2/3,0),x=1时,B(1,0)<br>S△ABP=1/2·(1-2/3)×1=1/6.<br><img src=""https://iknow-pic.cdn.bcebos.com/b58f8c5494eef01f5dd503c3e0fe9925bd317df6?x-bce-process=image/resize,m_lfit,w_600,h_800,limit_1"" max-height=""200"">"