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AEltusya
Dec 11, 2013, 01:25 AM
The sum of three successive terms of a geometric sequence is 35/2 while their product is 125. Find the three terms
ebaines
Dec 11, 2013, 07:23 AM
Given A = the first term and r is the ratio of successive terms, the brute force way to solve this is to set up two equations in two unknowns of A and r:
A + Ar + Ar^2 = 35/2
A(Ar)(Ar^2) = A^3r^3 = 125
This is a bear to solve. So here's a hint: note that 125 = 5^3, hence the product of Ar = 5. Try different values of A and r whose product is 5 ,and see what works.
AEltusya
Dec 12, 2013, 06:41 AM
Given A = the first term and r is the ratio of successive terms, the brute force way to solve this is to set up two equations in two unknowns of A and r:
A + Ar + Ar^2 = 35/2
A(Ar)(Ar^2) = A^3r^3 = 125
This is a bear to solve. So here's a hint: note that 125 = 5^3, hence the product of Ar = 5. Try different values of A and r whose product is 5 ,and see what works.
Awesome! Thanks :)