要详解v= u= what is |u×v|?v= u=v=u=what is |u×v|?v=u=what is |u×v|?开头就是这两道题不过没有写全,大神们直接看底下的补充吧

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要详解v= u= what is |u×v|?v= u=v=u=what is |u×v|?v=u=what is |u×v|?开头就是这两道题不过没有写全,大神们直接看底下的补充吧

要详解v= u= what is |u×v|?v= u=v=u=what is |u×v|?v=u=what is |u×v|?开头就是这两道题不过没有写全,大神们直接看底下的补充吧
要详解v= u= what is |u×v|?v= u=
v=
u=
what is |u×v|?
v=
u=
what is |u×v|?
开头就是这两道题不过没有写全,大神们直接看底下的补充吧

要详解v= u= what is |u×v|?v= u=v=u=what is |u×v|?v=u=what is |u×v|?开头就是这两道题不过没有写全,大神们直接看底下的补充吧
题目写全了吗,感觉是向量来着?

|u×v|就是以u和v为邻边的平行四边形的面积
v=<-4.3,-6.4,11.1>
u=<8.2,-2.1,4.2>
u×v=
| i j k |
|8.2 -2.1 4.2|
|-4.3 -6.4 11.1|
=3.57i-109.08j-61.51k
|u×v|=sqrt(3.57^2+109....

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|u×v|就是以u和v为邻边的平行四边形的面积
v=<-4.3,-6.4,11.1>
u=<8.2,-2.1,4.2>
u×v=
| i j k |
|8.2 -2.1 4.2|
|-4.3 -6.4 11.1|
=3.57i-109.08j-61.51k
|u×v|=sqrt(3.57^2+109.08^2+61.51^2)=125.278
v=<-8.9,-7,4.7>
u=<4.7,1.4,9.7>
u×v=
| i j k |
|4.7 1.4 9.7|
|-8.9 -7 -4.7|
=61.32i-53.43j-20.44k
|u×v|=sqrt(61.32^2+53.43^2+20.44^2)=83.861
计算式
u×v=
| i j k |
|ux uy uz|
|vx vy vz|
=(uy *vz-uz*vy)i-(ux*vz-uz*vx)j+(ux*uy-uy*vx)k
然后计算 sqrt[(uy *vz-uz*vy)^2+(ux*vz-uz*vx)^2+(ux*uy-uy*vx)^2]
要注意 u*v的方向与u和v成右手螺旋关系,并不在uv面上,而是垂直于uv面

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