So i have studied the rank method in matrix and how we can use it to find solutions or determine consistency of a system of equations, but despite having a qualititative idea,, i am unable to clearly understand why at all the method works, as to how the ranks have something to do with consistency,

What i do understand however is that the row transformations work because it is equivalent to manipulating multiple equations by multiplying different coefficients and then adding and subtracting,, we just do it inside the matrix,

From this i have deduced that ,,, probably since the rank of a matrix depends on number of non zero rows in echelon form,,

Thus if there remains a zero row in echelon form , it means that the particular row could be reduced to 0 simply through adding or subtracting (after multiplying scalars) with other rows OR that

the equations corresponding to other rows are equivalent to this one

OR

that the three equations are actually just two or whatever number of non zero rows,

IS my logic correct,, what are the holes in it? and can you please provide a pdf so i can understand with greater clarity?

Note by Mvs Saketh
6 years, 3 months ago

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Just curious to know how much marks are you getting in NSEP @Mvs Saketh

- 6 years, 3 months ago

Well 154 or 158 or 164, i should have been more accurate and learnt about the potentiometer,, its unfortunate, but i hope i qualify ,, and i have seen your comment,, well worry not,, not just for you, its a blow for everyone because this year NSEP was like totally different,, like there were hardly few mechanics questions, and most main chapters were missing,, and more importantly, that potentiometer passage problem was boring, its unfortunate,, the only good think about this paper was the pendulum passage, and ofcourse not to mention insufficient time,,so i think this is not a very good way to test ones innovation which is the real driving factor in INPHO, but its their choice,, i think i will focus on IIT JEE exam next

- 6 years, 3 months ago

Wow you have scored too good in the exam, not many people will be scoring in this range, also there are errors in the answer key right. @Mvs Saketh

- 6 years, 3 months ago

@ronak aggarwal- wait i didnt know answer key was released,, i just tallied with answer key,when you told it was released, i am getting shitty marks too 128 as per it,, but i am pretty sure that there are atleast 6 mistakes in answer key (may be more, i think, but surely 6) and so i believe , (the mistakes are in one pendulum question, one in the multiple correct choice, plants question, and one in the proportional to (1/T) question, also 69 th its a case of fresnel diffraction at sharp edge, not fraunholfer and,, and finally that polariser one is surely wrong) do you agree?

Also i think the coefficient of friction is around 0.5, not 0.41, what did you get?

ANd one questions answer is ridiculously wrong,, according to resonance,, speed of light decreases with temperature,,,

I think you should relax bro,, there are too many errors in it,, you are gonna get much better,, resonance has also done mistakes in other papers

- 6 years, 3 months ago

and yes in that magnet problem, if the question speaks about earths geographic north, then answer is Bh/4 or else its Bh/8,, resonance has done assuming that its earth magnetic north, so that one is a thing confusion , also resonance says that in that ABCD coil question,, in second case,, it says taht they are opposite with equal number of turns,, actually they are opposite with unequal number,, as if it was equal,, the bulb would not glow at all,,

And yes does it really behave as a NAND gate, seems like a NOR gate to me,, i might be wrong though

- 6 years, 3 months ago

But due to that errors only I am getting 128 , but actually my deserving marks are 120.

- 6 years, 3 months ago

Let it go , i have messed it up too, hopefully, we will not commit such mistakes in future

- 6 years, 3 months ago

I am getting 146

- 6 years, 3 months ago

Yeah..there are many mistakes....

- 6 years, 3 months ago