11But how do you get this determinant??
Wasnt the det supposed to be what i have written in #17
If the straight lines
x-1/k=y-2/2=z-3/3 and x-2/3=y-3/k=z-1/2
intersect at a point then k is equal to
(a)5
(b)2
(c)-2
(d)-5
-
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31 Answers
1but if u solved d other way, that is, equate both to A & B and eliminate A nd B to get K,
u also get a (2-k) in d denominator.
1@ R.I.P :
i think d first row of ur det shud hav been k 3 3
nd not k 2 3 as u hav done
11
11@ ani
this is done now
we have to take the determinant
|k 2 3 |
|3 k 2 |=0
|1 1 -2|
solving this we get k=-5 or k=5/2
so answer is D
11arey, someone.....atleast point out the mistake in my solution
11@ ani
I am sorry 4 the inconvenience
the option A is 5
now the question is PERFECT and the answer is FROM THE OPTIONS GIVEN
11RIPper, have a look at ur options, a and d are the same!!!(-5)
Maybe, option d was meant to be -5.5......
11here's my solution
PLS POINT OUT THE MISTAKE (IF THERE IS ANY)!!!!
11I solvd two times and both times, i got -11/2 ....same as asish....... RIPper, i think one of the options must be -11/2.......maybe u have posted the options for the next question....[3]
1machan.......... theres somethin else we ve to do.. or flaw in d question...
go n sleep.... u ll get everythin in mind...
;-)
1put
x-1/k=y-2/3=z-3/3=\lambda
x-2/3=y-3/k=z-1/2=\mu
equate any two variables in terms of\lambda& \mu
then solve it..
11here is something more direct if two lines intersect
lx2-x1 y2-y1 z2-z1l
l l1 m1 n1 l
l l2 m2 n2 l
the above determinant =0
(k-3)(2k+11)=0
But both roots are not in the options [2]
106i took let x-1/k=y-2/3=z-3/3 = s
So, x=sk+1, y=3s+2 and z=3s+3
Put them in x-2/3=y-3/k=z-1/2
u get sk-1/3 = 3s-1/k = 3s+2/2
if u equate 1 and 2,
then s=(k-3)/(k2-9) .. (i)
equate 1 and 3, u get
s=8/(2k-9) .. (ii)
Solving these two...
u get k=-11/2 and k=3 (this doesnt satisfy (i))
1hey.. loser.. i said i ve to leave now..
n wat i get is
(\lambda +\mu)(3-k)=0
doin in very urgency.. ignore if wron..
btw, loser tell ur name.. its not soundin gud to call u loser..
106@mirka .. k=3 will be elimintated bcz in sum pt. of my calculations k-3 was coming in the denom...
1yeah it'll take time ...
but u get d same thing ...
i mean, i can't make d same silly mistake twice !
1REALLY ??
but i checked it twice !
wat is it tht u r getting ? u get (2 - k) in denom ryt?
anyway, wats d answer 2 dis Q ??
1hey loser.. u don get dis by simplifyin.. i think u made a mistake somewhere..
pls do check it again..
