Examples : Equation of a line : Part 2 Video Lecture | Mathematics (Maths) Class 12 - JEE

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video please make sure that you have
watched part 1 to part 8 next take some
examples of a line passing through the
three points so you define the vector
and the Cartesian equation for the line
that passes through reason that is 0 0 0
and this point so I have my let's
suppose a vector has 0 ie plus 0 Z plus
0 K and V vector as 5i minus 2j minus 3y
i minus TJ plus so I have to find in
vector in Cartesian let's mine vector
vector is e plus lambda V minus E is 0 0
I plus 0 j plus 0 k plus lambda B is Phi
I minus 2j plus 3k minus 0 vector 0 I is
0 J 0 K this is nothing but lambda into
Phi I minus 2 J plus and this is my
equation in vector form correct
now let's find the vector in Cartesian
so that is the formula I know that in my
equation passes through X 1 Y minus y1
by y2 minus y1 is equal to 0-7 by itself
in my physics this equation for the line
that passes through x1 y1 z1 and x2 y2
z2 so here X 1 minus n 0 0 0 x2 y2 z2 is
5 minus 2 n 3 so let's put the value so
with this I get X minus X bar is 0 right
and X 2 is 5 X 1 is again 0 is equal to
Y minus y1 is 0 why do it this guy minus
2 minus 0 Z minus z1 is again 0 by Z 2
is 3 so what you get is X by 5 is equal
to Y by minus 2 is equal to Z by 3 and
this is my equation of the line in
Cartesian so I have two equation this
guy in vector form and this guy in
condition so now we know how to form the
equation of the line that passes through
viewpoint
we'll take some more examples to clear
conserve a refinery in the vector in
Cartesian form of the line the pass is
to these two points here it doesn't pass
at origin it has two points let this be
a vector and this may be B so equation
I'm applying something but K vector plus
lambda into V vector minus a vector
correct
a vector is what 3 minus 2 minus 5 that
is 3i minus TJ minus 5
he his director last lambda into B
vector 3 minus 2 6 3 I minus 2 ej + 6 k
in all caps
-
a 3-2 - v 3i - TJ - correct so this is
my equation and if you solve this this
becomes 3i minus 3i becomes zero this is
3i minus TJ minus Phi k plus lambda into
3a minus 3i becomes 0 2 J minus 2
becomes 0 6 K minus minus Phi is 6 5 6
plus 5 is 11 right so with this I get 3i
minus 2j plus 11 lambda minus 5 okay
this is my equation of line in the
vector form correct I have to find the
equation of the line in the Cartesian
form so we know this is nothing but X
minus x1 by x2 minus x1 is equal to Y
minus y1 by y2 - y1 is equal to Z minus
Z 1 by Z 2 minus Z so let's put the
value X - X minus 3 so let me put the
value ray exposures and it will try to
expand by one side 1 3 minus 2 minus 5
and x 2 y 2 Z 3 minus 2 X 6 so X 1 is 3
by X 2 is 3 minus X 1 is 3 this is equal
to Y minus y1 is minus 2 so y plus 2 it
becomes Y 2 is minus 2 minus y 1 is
again minus 2 equal to Z 2 minus Z 1 is
fine so this becomes plus 5 and this is
y 2 Z 2 - n to the 6 minus minus 5 that
is 6
this becomes X minus three by zero is
equal to y plus two pi 0 is 8 plus 5 and
that is masked
this is an equation of line in Cartesian
form for this condition thank you
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