FP3 Vectors Flashcards Preview

Maths > FP3 Vectors > Flashcards

Flashcards in FP3 Vectors Deck (15)
Loading flashcards...

Distance of point to line equation

(Point: c, Line: a + λb)


Distance between parallel lines equation

(Points on lines: a1/a2, Direction Vector: b)


Distance between skew lines equation

(Points on lines: a1/a2, Direction Vectors: b1/b2)


How to work out the angle between two planes

Use scalar product to find the angle between the normals (therefore a= n1, b=n2)


How to work out the angle between a line and a plane

Use the scalar product to find the angle between the line's direction and the plane's normal, and subtract this value from 90° 


How to work out line of intersection of 2 planes

The direction vector of the line of intersection is perpendicular to both plane's normals, therefore:

n1 x n2 = b

 Then use simputaneous equations to find a point on both planes and this will be a, for line equation in form:

r = a + λb


Distance of point to plane

(Plane equation in form: r.n=d where n is the normal, r is a general point. Position of point: a)

Use equation: Distance=


Area of triange


Area of Parallelogram


Volume of Parallelepiped

Where a and b represent vector sides of the parallelogram at the base and c represets the vector upwards in the 3rd dimension:  

Note: a.(bxc) = b.(cxa)


Volume of Tetrahedron

Same term definitions as volume of parallelepiped


Vector cross product formula

Where n stands for a unit vector perpendicular to both a and b. (in the direction that a right handed screw would move when turned a -> b) 

Note: b x a = -a x b, and to find a unit vector, divide the vector by it's magnitude. 


What is an alternate equation for a straight line in vector form?

(r-a) x b= 0

Can also be written as rxa - axb = 0 and hence as





What are the different forms for the eqaution of a plane?

r.n=a.n (r.n=d)

(which can be converted to catesian form by inputting r= xi+yj+zk)

r= a + λb + μc 

Where a is the position vector of a point in the plane, b and c are non-parallel vectors in the plane and r in the position vector a general point on the plane. 


 How to find the point of intersection of a line and a plane. 

Enter the line in column matrix form and substitute for r in the plane's eqation, r.n=a.n .