MY CART (5)

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: R

There are no items in this cart.
Continue Shopping

X

“Hurray! You have won the gift voucher. Redeem your points now."

X

                   

let a, b and c are unequal real positive numbers such that 2b = a + c, then roots of ax^2 + 2bx + c = 0 are


(i) real and equal (ii) Real and distinct (iii) imaginary (iv) nothing definite can be said


Plz explain

4 years ago

Share

Answers : (3)

                                        

Dear student,


2b=a+c


Sum of the roots=-2b/a


Product=c/a


This shows the roots are real and distinct...








Please feel free to ask your queries here. We are all IITians and here to help you in your IIT JEE preparation.


All the best.


Win exciting gifts by answering the questions on Discussion Forum. So help discuss any query on askiitians forum and become an Elite Expert League askiitian.


Now you score 5+15 POINTS by uploading your Pic and Downloading the Askiitians Toolbar  respectively : Click here to download the toolbar..


 


Askiitians Expert


Sagar Singh


B.Tech, IIT Delhi


sagarsingh24.iitd@gmail.com







4 years ago
                                        

for any quadratic eq  ax2+bx+c roots are given by


 X = {-b+_ D)/2a


D =discriminant = (b2-4ac)1/2


our eq is ax2+2bx+c so


D = {(2b)2-4ac)1/2 ........1


2b = a+c  (given)


so , (2b)2 = (a+c)2 ...........2


putting  eq2 in eq1


D = { (a+c)2 - 4ac}1/2  =  { a2+c2-2ac}1/2 ={(a-c)2}1/2 =a-c


now roots are


 X = (-2b +_ D}/2a = {-2b + (a-c)}/2a     or        {-2b-(a-c)}/2a                                   


                           = -c/a                      or        -1                                  (on putting 2b =a+c )


so the roots are unequal & real


option (ii) is correct

4 years ago
                                        

the equation is ax^2+2bx+c=0


the discriminant is= B^2-4AC


A=a,B=2b,C=c


discriminant= 4b^2-4ac


but 2b=a+c, therefore (2b)^2=(a+c)^2


= (a+c)^2-4ac


=a^2+c^2+2ac-4ac


=a^2+c^2-2ac


=(a-c)^2, which is always greater than zero


therefore roots are real and distinct

4 years ago

Post Your Answer

More Questions On IIT JEE Entrance Exam

Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!!
Click Here for details
I will be appearing for IITJEE-2016. I am very good at the concepts. But I am too slow. Any suggestions? How can I improve my speed?
 
 
Dear student, Please try to solve as many as questions as possible. By this definetly your speed will increase. Thanks.
  img
Vijay Mukti 24 days ago
 
Stay focused on your studies and keep in mind that one must focus on Physics, Chem and Maths, try to fortify these three, take some coaching classes from a reputed place like Akash Inst...
 
Ayushmaan Vardhan 23 days ago
 
the only way to improve your speed is by lots of practice and have one thing in mind and never think that your concepts are strong ther are many students whose concepts are upto msc level...
 
Prajwal Kavad 22 days ago
I cleared mains but could not clear advanced this year. Next year can i directly take advanced or should i again write mains?
 
 
Dear Student, You will have to reappear for the JEE mains as well. Thanks.
  img
Vijay Mukti 24 days ago
 
You can’t take advanced, you’ll have to take mains first and keep some tips in mind –Stay focused on your studies and keep in mind that one must focus on Physics, Chem and Maths, try to...
 
Ayushmaan Vardhan 23 days ago
sir i m a dropper how should i make my plans so that i can crack iit
 
 
Stay focused on your studies and keep in mind that one must focus on Physics, Chem and Maths, try to fortify these three, take some coaching classes from a reputed place like Akash Inst...
 
Ayushmaan Vardhan 14 days ago
 
Try to make out what are the weaker points in the field of PCM, work harder on them, download concerned topic papers and practice them, define a proper time for practice, join some reputed...
 
Ayushmaan Vardhan 9 days ago
 
every person has its special plannings we get success by our on tools so think it over .. and analyse what is your daily routine and plan it by keeping ur daily needs and things to prepare...
 
Gayatri Jayesh Bondriya 10 days ago
Bits pilani chemical engineering or DTU mathematics and computing? ...placements and jobs to be the priority. PLZZ answer soon
 
 
Bro. BITs is a private college it will charge a very high fee and will not give you satisfaction instead of this DTU is a govt. college so I prefer you to take DTU math and comp. as it will ...
 
Akshit Matthew 14 days ago
i have 120 marks in jee main and 90.4 in cbse board can i get sgsits in 2 nd counselling
 
 
I recommend you to keep track of the outcome of counselling rounds, may be you crack in there this time, if not then don’t be disheartened, there are ample of renowned institutions where...
 
Soneel Verma 7 days ago
 
HOW COULD I KNOW ABOUT MYSTATUS IN COUNSELLING ITS ALL ONLINE
 
aditya lahariya 8 days ago
 
sir please reply soon
 
aditya lahariya 9 days ago
got rank 374001 in st category , will i get nit kurukshetra and nit kurukshetra is located in my home state .since previous year home state opening and closening rank was around 4 lac...
 
 
According to csab the previous year maximum closing rank for NIT kurukshetraafter 4 th round was in and around 8,50,000 for ST category. So you’ll definitely get it
  img
Avinash 24 days ago
 
I think you will get it , but to be on a safe side why don’t you visit the ofiicial website JEE Mains and get to know where do you stand, you can also check it at other places too where you ...
 
Ayushmaan Vardhan 23 days ago
View all Questions »