Q. 445.0( 1 Vote )

The sum of first three terms of a G.P. is and their product is 1. Find the common ratio and the terms.



Answer :


Let three terms in G.P. are

Their product = = 1

or a3 = 1

or a = 1

Again =

or =

or = r

or 1 + 10r + 10r2 = 39r

or 10r2 - 29r + 10

or 10r2 - 25r – 4r + 10 = 0

or 5r(2r – 5) – 2(2r – 5) = 0

or (2r – 5) (5r – 5) = 0

or r =

Case (i) When r =

Numbers are

Case (ii) When r =

Numbers are

or or

Hence three numbers are or

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Interactive quiz on inequalities involving AM and GM45 mins
Check Your progress Part 2| Interactive Quiz: Sequence & Series47 mins
Sequence & Series (Lecture 1)56 mins
Sequence & Series (Lecture 5)42 mins
Sequence & Series (Lecture 7)37 mins
Sequence & Series (Lecture 6)42 mins
Use of sigma in finding sum42 mins
Trigonometric Series45 mins
Quick Recap lecture of Sequence & Series56 mins
General Term of Miscellaneous progression46 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses