\(曲面z=f(x,y)在(x_0,-y_0)的切平面方程是(\,)\) A: \[z=f(x_0,y_0)+f_x(x_0,y_0)(x-x_0)+f_y(x_0,y_0)(y-y_0)\] B: \[z=f(x_0,-y_0)-f_x(x_0,-y_0)(x-x_0)-f_y(x_0,y_0)(y+y_0)\] C: \[z=f(x_0,-y_0)+f_x(x_0,-y_0)(x-x_0)-f_y(x_0,-y_0)(y+y_0)\] D: \[z=f(x_0,-y_0)+f_x(x_0,-y_0)(x-x_0)-f_y(x_0,-y_0)(y-y_0)\]
\(曲面z=f(x,y)在(x_0,-y_0)的切平面方程是(\,)\) A: \[z=f(x_0,y_0)+f_x(x_0,y_0)(x-x_0)+f_y(x_0,y_0)(y-y_0)\] B: \[z=f(x_0,-y_0)-f_x(x_0,-y_0)(x-x_0)-f_y(x_0,y_0)(y+y_0)\] C: \[z=f(x_0,-y_0)+f_x(x_0,-y_0)(x-x_0)-f_y(x_0,-y_0)(y+y_0)\] D: \[z=f(x_0,-y_0)+f_x(x_0,-y_0)(x-x_0)-f_y(x_0,-y_0)(y-y_0)\]
\(设曲面f(x,y,z)=0,且在P(x_0,y_0,z_0)处有定义,则曲面在P处有法向量。\)
\(设曲面f(x,y,z)=0,且在P(x_0,y_0,z_0)处有定义,则曲面在P处有法向量。\)
\(设曲面f(x,y,z)=0,函数f(x,y,z)有连续的偏导数吗,且在P(x_0,y_0,z_0)处有定义,则曲面在P处有法向量。\)
\(设曲面f(x,y,z)=0,函数f(x,y,z)有连续的偏导数吗,且在P(x_0,y_0,z_0)处有定义,则曲面在P处有法向量。\)
\(二元函数f(x,y)在(x_0,y_0)沿任何方向导数存在,则f(x,y)在该点可微\)
\(二元函数f(x,y)在(x_0,y_0)沿任何方向导数存在,则f(x,y)在该点可微\)
\(函数f(x,y)在点(x_0,y_0)处可微,则f(x,y)在该点处的任意方向导数存在\)
\(函数f(x,y)在点(x_0,y_0)处可微,则f(x,y)在该点处的任意方向导数存在\)
若方程$\left\{ {\matrix{ {y' = f(x,y)} \cr {y({x_0}) = {y_0}} \cr } } \right.$中的$f(x,y)$满足利普希茨条件,则欧拉格式与改进的欧拉格式都收敛。
若方程$\left\{ {\matrix{ {y' = f(x,y)} \cr {y({x_0}) = {y_0}} \cr } } \right.$中的$f(x,y)$满足利普希茨条件,则欧拉格式与改进的欧拉格式都收敛。
将一个年份输入y,判断闰年的条件表达式是? A: y%4=0 and y%100!=0 B: y%400=0 C: (y%4=0 and y%100!=0) and (y%400=0) D: (y%4=0 and y%100!=0) or (y%400=0)
将一个年份输入y,判断闰年的条件表达式是? A: y%4=0 and y%100!=0 B: y%400=0 C: (y%4=0 and y%100!=0) and (y%400=0) D: (y%4=0 and y%100!=0) or (y%400=0)
下列语句与y=(x>;0?1:x<;0?-1:0);语句功能相同是( ) A: if (x) if(x>;0) y=1; else if(x<;0) y=-1;else y=0; B: y=-1; if(x>;0) y=1; else y=-1; C: if (x>;0) y=1; else if(x<;0) y=-1; else y=0; D: y=0; if(x>;=0) y=1;else if(x==0) y=0; else y=-1;
下列语句与y=(x>;0?1:x<;0?-1:0);语句功能相同是( ) A: if (x) if(x>;0) y=1; else if(x<;0) y=-1;else y=0; B: y=-1; if(x>;0) y=1; else y=-1; C: if (x>;0) y=1; else if(x<;0) y=-1; else y=0; D: y=0; if(x>;=0) y=1;else if(x==0) y=0; else y=-1;
【单选题】与“y=(x>0?x:x<0?-x:0);”的功能相同的if语句是______。 A. if(x>0) y=x; else if(x<0) y=-x; else y=0; B. if(x) if(x>0) y=x; else if(x<0) y=-x; else y=0; C. y=-x; if(x) if(x>0) y=x; else if(x==0) y=0; else y=-x; D. y=0; if(x>=0) if(x>0) y=x; else y=-x;
【单选题】与“y=(x>0?x:x<0?-x:0);”的功能相同的if语句是______。 A. if(x>0) y=x; else if(x<0) y=-x; else y=0; B. if(x) if(x>0) y=x; else if(x<0) y=-x; else y=0; C. y=-x; if(x) if(x>0) y=x; else if(x==0) y=0; else y=-x; D. y=0; if(x>=0) if(x>0) y=x; else y=-x;
表达式!(x>0||y>0)等价于( ) A: !x>0||!y>0 B: !(x>0)||!(y>0) C: !(x>0)&&!(y>0) D: !x>0&&!y>0
表达式!(x>0||y>0)等价于( ) A: !x>0||!y>0 B: !(x>0)||!(y>0) C: !(x>0)&&!(y>0) D: !x>0&&!y>0