MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

⇐ BackProceed to Checkout ⇒
There are no items in this cart.
Continue Shopping
Menu
Grade: 11 
        
if 1/a,1/b,1/c,1/d are in AP prove that 
ab + bc +cd = 3ad
2 years ago

Answers : (2)

Nishant Vora
IIT Patna
askIITians Faculty
2468 Points 
							Hey student,

You can find a similar question here

http://www.askiitians.com/forums/Algebra/if-a-b-c-d-are-in-hp-then-prove-that-ab-bc_95273.htm
2 years ago
mycroft holmes
272 Points 
							
Dividing by abcd, we have to prove that \frac{1}{cd}+\frac{1}{ad}+\frac{1}{ab} = \frac{3}{bc} or
 
that \frac{1}{cd}+\frac{1}{ad}+\frac{1}{ab} + \frac{1}{bc} = \frac{4}{bc}
 
LHS can be factorised as \left(\frac{1}{c}+\frac{1}{a} \right) \left(\frac{1}{b} + \frac{1}{d} \right)
 
Since the given numbers are in AP we have 
\left(\frac{1}{c}+\frac{1}{a} \right) = \frac{2}{b}; \left(\frac{1}{b} + \frac{1}{d} \right) = \frac{2}{c}
 
Hence we get \left(\frac{1}{c}+\frac{1}{a} \right) \left(\frac{1}{b} + \frac{1}{d} \right) = \frac{2}{b} \times \frac{2}{c} = \frac{4}{bc}
2 years ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies

Other Related Questions on Algebra

which of the following is the solution of |2x+5|-|x-3|>=| x +8 |? Answer & Earn Cool Goodies
If z1 not equal to z2 not equal to z3 not equal to z4 in C infinity the cross ratio (z1 z2 z3 z4) is... Answer & Earn Cool Goodies
Sum of n terms of any A.P is n^2+2n . Find the first term and common difference
Please answer by algebraic method.................. ....................
@arun now plz tell big bro...as soon as possible i have sent the pic
View all Questions »


Course Features

  • 731 Video Lectures
  • Revision Notes
  • Previous Year Papers
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Test paper with Video Solution


Course Features

  • 101 Video Lectures
  • Revision Notes
  • Test paper with Video Solution
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Previous Year Exam Questions


Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers To Win!!! Click Here for details