no dude...there is no flaw in the reasoning. root of a positive integer can never be negative, though square of a negative number is positive...
so root of a positive number is only positive...and root of a negative no is imaginary or complex...
and u get ans as 1 when x is 5 and -1 when x= -5 and not +/- 1 when x is 5 and -5....
sign is taken care by x in denominator..hence the answer is E....and not bcoz it can be 1 and -1 simultaneously...
I choose to disagree with you ,Bhavin. Root of a positive number CAN be positive or negative and it is so downright obvious that i don't see the point in arguing over it anymore.Why are you not getting it?Isn't root of 25 = +5 or -5?
there are 7 people out of 12 who can be seated anywhere, therefore factorial 7 or 7! which is equal to 5040 there are 3 people who can sit on only 1 side, therefore total options = factorial 3 = 6 there are 2 people who can sit on the other side only, therefore total options = factorial 2 = 2
total = 7! x 3! x 2! = 60480..hope its clear!
Can Someone plz help me with this? A group of 8 man r to b chosen from 12 men for rowing out of which 3 men can row on one side only & 2 can row on the other side only. Find the numbr of ways of arranging the crew with 4 members on each side. 40320 30240 60480 10080 20640
PS: the answer given is 60480 but can someone plz give proper explaination.
I choose to disagree with you ,Bhavin. Root of a positive number CAN be positive or negative and it is so downright obvious that i don't see the point in arguing over it anymore.Why are you not getting it?Isn't root of 25 = +5 or -5?
it is very obvious to me as well...root 25 cannot be -5...its not about argument...it is about clearing the concept...i would be glad if seniors could clarify this...it would be gud if somebody can clear this ambiguity...
it is very obvious to me as well...root 25 cannot be -5...its not about argument...it is about clearing the concept...i would be glad if seniors could clarify this...it would be gud if somebody can clear this ambiguity...
i dont know whether you guys will consider me senior or not But still i will try to explain If we take square of 5 it is 25 and for -5 it is also 25 So when we take suare root of a no. we generally put +/- sign before it Like in quadratic equation remember the roots formula for roots they also consider both the +ve and -ve value for D that is b^2 - 4ac hope this clears the confusion
Sillyfool and yes there are no stupid questions and arguments so keep discussing as long as you ppl dont start fighting
there are 7 people out of 12 who can be seated anywhere, therefore factorial 7 or 7! which is equal to 5040 there are 3 people who can sit on only 1 side, therefore total options = factorial 3 = 6 there are 2 people who can sit on the other side only, therefore total options = factorial 2 = 2
total = 7! x 3! x 2! = 60480..hope its clear!
Can Someone plz help me with this? A group of 8 man r to b chosen from 12 men for rowing out of which 3 men can row on one side only & 2 can row on the other side only. Find the numbr of ways of arranging the crew with 4 members on each side. 40320 30240 60480 10080 20640
PS: the answer given is 60480 but can someone plz give proper explaination.
yaar the answer is right but there is something fishy about the soln I mean you have not considered that we have to select 8 ppl anywhere but still its the right answer , well i am not saying this is wrong method or something but i will request some1 to post another soln cause i m tryin on the same and still not able to figure out
I choose to disagree with you ,Bhavin. Root of a positive number CAN be positive or negative and it is so downright obvious that i don't see the point in arguing over it anymore.Why are you not getting it?Isn't root of 25 = +5 or -5?
i dont know whether you guys will consider me senior or not But still i will try to explain If we take square of 5 it is 25 and for -5 it is also 25 So when we take suare root of a no. we generally put +/- sign before it Like in quadratic equation remember the roots formula for roots they also consider both the +ve and -ve value for D that is b^2 - 4ac hope this clears the confusion
Sillyfool and yes there are no stupid questions and arguments so keep discussing as long as you ppl dont start fighting
hey sillyfool...absolutely true...more we discuss, more we learn..evtng is in good spirit..
yes..everybody knows..square of -ve is +ve..but root of positive conventionally means principal square root...which is positive...
hope this clears some ambiguity...keep discussing...
Conventionally Bhavin? :)
Come on man, if u r tellin me that you will ignore the negative root just because it is not conventional, u would b really unfair to all the negative numbers out there (and that is about 50% of all the numbers on the number line u know?).
Now, i said i didnt want to argue over this coz u dont seem too inclined to understand the little fact that a positive number has 2 roots-a positive and a negative.All Im trying to do is to clear a confusion u have but then ultimately it's upto u whether u want to believe me or not.
Come on man, if u r tellin me that you will ignore the negative root just because it is not conventional, u would b really unfair to all the negative numbers out there (and that is about 50% of all the numbers on the number line u know?).
Now, i said i didnt want to argue over this coz u dont seem too inclined to understand the little fact that a positive number has 2 roots-a positive and a negative.All Im trying to do is to clear a confusion u have but then ultimately it's upto u whether u want to believe me or not.
Thanks!
dude...its not dat i am not understanding...n the other thing is that i am not arguing with u..its v much a valid discussion..
its like perception...u can either say...glass is half filled or half empty...choice is yours... n its not about believing or not...
in terms of mathematics, whenever u solve ...its only postive root...
n keeping GMAT in mind ... on DS ques....if ques is what is value of x???
n statement 1 is root of 25....this statement is very much sufficient to solve the problem..
Conventionally, yes, we take only the positive root. But that does not mean that -5 is not a root of 25. And as far as DS questions in GMAT or CAT, IMO, we have to consider both the roots - postive and negative.
In my opinion, KingCat is totally right. If you're asked the root of 25, both +/-5 will definitely have to be considered. However yes, conventionally, only the positive root is considered.
P.S. Folks, if we have a disagreement on some issue, let's try and use the PM feature to sort it out, instead of fighting it out in public. There are other users who are here to get the maximum value from this thread, and it would hurt them if we keep on disagreeing with each other. :rockon:
In my opinion, KingCat is totally right. If you're asked the root of 25, both +/-5 will definitely have to be considered. However yes, conventionally, only the positive root is considered.
P.S. Folks, if we have a disagreement on some issue, let's try and use the PM feature to sort it out, instead of fighting it out in public. There are other users who are here to get the maximum value from this thread, and it would hurt them if we keep on disagreeing with each other. :rockon:
Hey sumit, we were not arguing over movie reviews or something irrelevant to the thread.Bhavin here had a little misconception and i think you should help someone when u can. And that is what this thread is all about: problem solving DISCUSSIONS.As long as it is useful to someone, it's fine.
PS:this could not be sorted in PM coz bhavin wanted SOMEONE ELSE to comment.He doesn't believe me:(
Hey sumit, we were not arguing over movie reviews or something irrelevant to the thread.Bhavin here had a little misconception and i think you should help someone when u can. And that is what this thread is all about: problem solving DISCUSSIONS.As long as it is useful to someone, it's fine.
PS:this could not be sorted in PM coz bhavin wanted SOMEONE ELSE to comment.He doesn't believe me:(
ok guys...lets put an end to this discussion...we had no intentions to spam the thread..i was looking for genuine discussions...lets move ahead and solve more problems...
hi rajkumar i guess the answer to the question is e when you take square of a no. and then take square root it can have either of the two values i mean +x or -x so it becomes x as x
0 so divided by x becomes the option e
hope this helps Sillyfool
/x is 5/-5 = -1 i.e x|/x
if x=5, x^2=25 & 25^1/2=5 i.e /x is 5/5=1 i.e x/x
Hence x/x satisfies for +ve n -ve nos...Ans E
Well Bhavin is absolutely correct! These are basics. sqrt(25) is only and only +5 and nver... -5. In the question we are taking |x to ensure that it stays +ve, irrespective of what x we choose. When u r asked what is the value of x, given that x^2 = 25, then x=+5, and -5 are correct. There is no convention and all. And not to forget that sqrt of a negative number is not defined at all.