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Yahoo!
 3 years ago
if z>= 3 the least value of z + 1/z is?
Yahoo!
 3 years ago
if z>= 3 the least value of z + 1/z is?

This Question is Closed

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1i think we need to use x+y>x+y but not sure.

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0But wat Does that Least Value For?

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1i m just trying.... if z>=3 what can u say about 1/z ??

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0z ( 1/z) > = z  1/z

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0I Did nt Understand....wat is here Least..""

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1means z+1/z is > = 'some number' u need to find that number.

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1but z+1/z <= z+1/z how did u get > sign there ?

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0u see..i have inserted a ve there....Since it asks for least value."

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.0Hmm.. Am I right for this: z ≥ 3 i.e. z ≥ 3 or z ≤ 3 ?

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1i think z is complex here, isn't it @Yahoo! ??

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1so z>= 3 represents region outside the circle with radius 3.....if i have not misinterpreted

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.0Wow! Something I don't know! I'm sorry!!

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1because of > sign, if < then inside.

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1i got something from yahoo answers , trying to understand it, see if that makes some sense to u..... http://in.answers.yahoo.com/question/index?qid=20100423221137AAAgV9K

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0i think we have to find the least dist b/w Circles

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0@hartnn i Did nt Understand.....Can u Explain...

Ishaan94
 3 years ago
Best ResponseYou've already chosen the best response.0\[z \geq 3\implies z\leq3\;or\;z\geq3\] \(\leftz + \frac1z\right\) is just a symmetrical hyperbola about Yaxis. If you're well versed with hyperbola you will get the idea of the graph with constraint \(z\geq3\).

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0lol...i Dont knw Hyperbola....

Ishaan94
 3 years ago
Best ResponseYou've already chosen the best response.0Okay. \[x + \frac1x\] \(x\) is ever increasing, so to find the minima of \(x + \frac1x\) you should find value for which \(x\) is minimum i.e 3 as \(1/x\) is decreasing for \(x>1\).

Ishaan94
 3 years ago
Best ResponseYou've already chosen the best response.0Important to note \(1/x\) is decreasing not negative.

Ishaan94
 3 years ago
Best ResponseYou've already chosen the best response.0Negative with respect to \(x\).

Pallavi06
 3 years ago
Best ResponseYou've already chosen the best response.0express Z= x+ iy.......and its mod value is suar root of x^2 +y^2.....now mod of Z+1 can be expressed as (x+1 )+ iy......and then solve it.....i know its very lengthy but it works when u have no other option....

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0If r is the modulus of z, then z+ 1/z >= r  1/r. Now the minimum of r  1/r for r>=3 is clearly 3  1/3 = 8/3. The minimum for z+1/z is attained if z = 3 and if z and 1/z have opposite directions. Take z = 3i so that z = 1/3i =  i / 3, and the minimum 8/3 is attained for that value. Can u Explain this!

Ishaan94
 3 years ago
Best ResponseYou've already chosen the best response.0I was afk. Complex Numbers?

Ishaan94
 3 years ago
Best ResponseYou've already chosen the best response.0away from the keyboard.

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0Yes.. it is Complex Numbers

Pallavi06
 3 years ago
Best ResponseYou've already chosen the best response.0let Z= x + iy and try to get value of mod 1/z

Pallavi06
 3 years ago
Best ResponseYou've already chosen the best response.0if mod z is r then ull get mod i/z as 1/r.....

Ishaan94
 3 years ago
Best ResponseYou've already chosen the best response.0I will be back, my trackpad isn't working somehow.

Vaidehi09
 3 years ago
Best ResponseYou've already chosen the best response.0shouldn't it be this way? or is something wrong with this? dw:1347108277591:dw

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1if its <= then its max value , not least value.

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0The answer should be 8/3

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1and yes,thats the correct way to find max value.

Yahoo!
 3 years ago
Best ResponseYou've already chosen the best response.0lol.....Can we Do like this z ( 1/z) > = z  1/z

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.1is this true ? xy >= xy if yes, then u can do it like that.
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