The Student Room Group

Proving two vectors are coplanar and finding the Cartesian equation of the plane whic

Show that r = 3i+2j+k+t(-i+2j+k) and r=3i+9j+2k+t(2i+3j-k) are coplanar and finding the Cartesian equation of the plane which contains them.

Posted from TSR Mobile
Original post by SpanishTashman
Show that r = 3i+2j+k+t(-i+2j+k) and r=3i+9j+2k+t(2i+3j-k) are coplanar and finding the Cartesian equation of the plane which contains them.

Posted from TSR Mobile




Posted from TSR Mobile
Reply 2


crossing their direction vectors and dotting the answer with any of the 2 direction vectors should give you zero if coplanar
Okay I've crossed the direction vectors and got -5i+j-7k, how would I go about dotting that? As in which vectors represents a and n?

Posted from TSR Mobile
Original post by TeeEm
crossing their direction vectors and dotting the answer with any of the 2 direction vectors should give you zero if coplanar


Okay I've crossed the direction vectors and got -5i+j-7k, how would I go about dotting that? As in which vectors represents a and n?

Posted from TSR Mobile
Reply 5
Original post by SpanishTashman
Okay I've crossed the direction vectors and got -5i+j-7k, how would I go about dotting that? As in which vectors represents a and n?

Posted from TSR Mobile


Ok

bit busy here

if the lines intersect then they are Coplanar since they are not parallel

So find intersection

the cross product of their direction then is the normal of the plane they define

use the intersection point and the normal to find plane
c4?
Original post by coolgamer
c4?


Nope FP3.

Posted from TSR Mobile
Original post by TeeEm
Ok

bit busy here

if the lines intersect then they are Coplanar since they are not parallel

So find intersection

the cross product of their direction then is the normal of the plane they define

use the intersection point and the normal to find plane


Sorry to have been a pain, thanks for the useful help.

Posted from TSR Mobile
Reply 9
Original post by SpanishTashman
Sorry to have been a pain, thanks for the useful help.

Posted from TSR Mobile


no pain

Just doing my own work as well

Quick Reply

Latest