JEE MainMathematicsSequences and SeriesNumerical+4 / −1
Let be a of increasing positive numbers. If the product of fourth and sixth terms is 9 and the sum of fifth and seventh terms is 24, then is equal to .
Numerical answer
View written solutionFree
Correct answer: 60
Let the GP be with and since the terms are increasing positive numbers.
We are given:
-
Product of 4th and 6th terms is : But so (since all terms are positive).
-
Sum of 5th and 7th terms is : Using , Since ,
Now compute the required expression:
Step 1: Find
Step 2: Find
Rewrite as
Step 3: Find
This is already given:
Step 4: Add all parts
Therefore, the required integer is
More from Sequences and Series
- Let and , be two G.P.s with common ratios and respectively such that and . Let . If and …2023 · Numerical
- Let and be in A.P., and and be in G.P. If the sum of first 20 terms of an A.P., whose first term is and the common difference is is …2023 · MCQ
- If the sum and product of four positive consecutive terms of a G.P., are 126 and 1296 , respectively, then the sum of common ratios of all such GPs is2023 · MCQ
- Let be in A.P. If and , then is equal to …2023 · Numerical
- Let be an A.P. If , the product is minimum and the sum of its first terms is zero, then is equal to :2023 · MCQ
- If , where n is an even integer, is an arithmetic progression with common difference 1, and , then n is equal to :2022 · MCQ
- Let x, y > 0. If x3y2 = 215, then the least value of 3x + 2y is2022 · MCQ
- Let be two non-zero real numbers. If and are the roots of the equation and and s are the roots of the equation , such that …2022 · Numerical