sign up I login
 advanced
refer a friend - earn nickels!!

Ask & Discuss Questions with Community & Experts

Moderation Team
 90 chars left    advanced
Ask iit jee aieee pet cbse icse state board experts Expert Question: a good Q . on functions
Forum Index -> Algebra like the article? email it to a friend.  
Author Message
akshay.khare91 (480)

Blazing goIITian

Olaaa!! Perrrfect answer. 78  [123 rates]

akshay.khare91's Avatar

total posts: 574    
offline Offline

find the domain of


sin inverse [sec x]   where [.] represents the greatest integer functions..


I DONOT FOLLOW THE RULES I MAKE THEM TO FOLLOW ME.
    
amitp91 (302)

Blazing goIITian

Olaaa!! Perrrfect answer. 44  bad job dude!! I dont approve of this answer! 1  [87 rates]

amitp91's Avatar

total posts: 877    
offline Offline
it is -infinity to infinity



 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
amitp91 (302)

Blazing goIITian

Olaaa!! Perrrfect answer. 44  bad job dude!! I dont approve of this answer! 1  [87 rates]

amitp91's Avatar

total posts: 877    
offline Offline
rate if right



 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
akshay.khare91 (480)

Blazing goIITian

Olaaa!! Perrrfect answer. 78  [123 rates]

akshay.khare91's Avatar

total posts: 574    
offline Offline
nooo the ans. is [ (2n+1)pie) ] union [2npie , 2npie - pie /3 ]
where n belongs to integer.....

I DONOT FOLLOW THE RULES I MAKE THEM TO FOLLOW ME.
 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
vnkt.swaroop (353)

Blazing goIITian

Olaaa!! Perrrfect answer. 53  [97 rates]

vnkt.swaroop's Avatar

total posts: 311    
offline Offline
the range of secx is R-{-1,1}.but sin inverse x is defined for -1 to 1.so domain is null.
 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
vnkt.swaroop (353)

Blazing goIITian

Olaaa!! Perrrfect answer. 53  [97 rates]

vnkt.swaroop's Avatar

total posts: 311    
offline Offline
please rate me and tell whether my answer is true or false?
 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
pujasinghtwinkle (120)

Blazing goIITian

Olaaa!! Perrrfect answer. 20  [30 rates]

pujasinghtwinkle's Avatar

total posts: 348    
offline Offline

yup.........it is a null set i.e da function does nt exists as da value of  [sec x ] never lies b/w [-1 , 1]


 


& sin inverse x is defined only fr x = [-1 ,1]


EDIT-lozzzz ......made a mistake secx =-1 so dat  [sec x ] =[-1,1]


so domain aint null


 


 


 


 


 


what is this life so full of care ?
we have no time 2 stand & stare !!!!
--DAVIES--


laziness pays now.....
hard work L8ter....
but both pays ! !


If u can fill the unforgiving minute with sixty seconds worth of distance run;urs is da world n all dats in it----------->>>>a Russian who spend 7 yrs in siberia said dat the above lines helped sustain him




p.s. u wont loose ur rates if u will RATE me-------------->>>>>>



 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
rohitkuruvila (311)

Hot goIITian

Olaaa!! Perrrfect answer. 53  bad job dude!! I dont approve of this answer! 1  [78 rates]

rohitkuruvila's Avatar

total posts: 186    
offline Offline

the domain of sin -1 x is [-1,1]

sec x lies between [-infinity,-1] union [1,infinity]


sec x is equal to -1 at (2n+1)  ,so [sec x]=-1 at this value

[sec x] =1 means sec x lies between [1,2)


that happens  when x lies between [0, /3) ,general eq. is [2n ,2n +-  /3)


so the final answer is (2n+1)  union [2n ,2n +-  /3)

 this reply: 7 points  (with Olaaa!! Perrrfect answer.   in 2 votes )   [?]
 
You have to be logged on to rate
  
vasanth (2315)

Blazing goIITian

Olaaa!! Perrrfect answer. 401  [556 rates]

vasanth's Avatar

total posts: 517    
offline Offline

the inverse exists only if


[secx] = -1 & +1


so


secx belongs to [-1,0) U [1,2)


in [-1,0) only {-1} is possibl--------so x= (2n+1)pi


in [1,2)-----x takes values from [2n pi , 2n pi +- sec inverse2)


            --------------[2n pi , 2n pi +- pi/3)


finally take the union....


hey y r u guyz missing the +- .........sec follows cos .......nd so wen u take gen solution u'll have( 2npi +-  alpha)


Hope that Helps!


dbznfreak---watchin episodes for 6 yrs--movin on to dbgt

<TABLE CELLSPACING="1" CELLPADDING="1" BORDER="0">
<TR><TD>


<DIV ALIGN="right">Animated Letters</DIV></TD></TR></TABLE>
 this reply: 17 points  (with Olaaa!! Perrrfect answer.   in 4 votes )   [?]
 
You have to be logged on to rate
  
vnkt.swaroop (353)

Blazing goIITian

Olaaa!! Perrrfect answer. 53  [97 rates]

vnkt.swaroop's Avatar

total posts: 311    
offline Offline
sorry,domain is all the values of -1&1.
 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
akshay.khare91 (480)

Blazing goIITian

Olaaa!! Perrrfect answer. 78  [123 rates]

akshay.khare91's Avatar

total posts: 574    
offline Offline
but @ vasant , rohit
the secx is [1,2) not only in 0 to pie/3 it is also in -pie/3 to 0
so general solution can be ( 2npie - pie/3 , 2npie + pie/3)..
that is where my ans is not matching....

I DONOT FOLLOW THE RULES I MAKE THEM TO FOLLOW ME.
 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
rohitkuruvila (311)

Hot goIITian

Olaaa!! Perrrfect answer. 53  bad job dude!! I dont approve of this answer! 1  [78 rates]

rohitkuruvila's Avatar

total posts: 186    
offline Offline

ya, sorry abt that .i forgot that in cos you have to take the +- part in the general eqn.

 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
vasanth (2315)

Blazing goIITian

Olaaa!! Perrrfect answer. 401  [556 rates]

vasanth's Avatar

total posts: 517    
offline Offline

hi @akshaykhare




 


i have also got the same answer..........i used +- jus to make the sign omitters kno their mistakes.......




 


i stated [2n pi , 2npi + - pi/3)




 


unstead of my +- u've used the conventional method-------( 2n pi - pi/3, 2npi + pi/3)--------




 


we've got the same answer!


dbznfreak---watchin episodes for 6 yrs--movin on to dbgt

<TABLE CELLSPACING="1" CELLPADDING="1" BORDER="0">
<TR><TD>


<DIV ALIGN="right">Animated Letters</DIV></TD></TR></TABLE>
 this reply: 12 points  (with Olaaa!! Perrrfect answer.   in 3 votes )   [?]
 
You have to be logged on to rate
  
akshay.khare91 (480)

Blazing goIITian

Olaaa!! Perrrfect answer. 78  [123 rates]

akshay.khare91's Avatar

total posts: 574    
offline Offline
sooo ...how the ans .is going come ...????????

I DONOT FOLLOW THE RULES I MAKE THEM TO FOLLOW ME.
 this reply: 0 points  (with Olaaa!! Perrrfect answer.   in 0 votes )   [?]
 
You have to be logged on to rate
  
akshay.khare91 (480)

Blazing goIITian

Olaaa!! Perrrfect answer. 78