Q8. If 7 = 5 + 17 (5 + α) + 721 (5 + 2α) + 731 (5 + 3α)+ ∞, then the value of α is : (1) 6 (2) 6 7 (3) 1 (4) 1 7
What This Question Tests
This question requires recognizing the given series as an Arithmetic-Geometric Progression (AGP) and then using its sum formula or method to find the unknown parameter.
Concepts Tested
Formulas Used
S = a/(1-r) + dr/(1-r)^2 (for A.G.P. when |r|<1)
📚 NCERT Sections This Tests
2.1 — Two Charges 5 × 10–8 C And –3 × 10–8 C Are Located 16 Cm Apart. At
Physics Class 11 · Chapter 2
2.1 Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero.
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
8.17 — Complete Each Synthesis By Giving Missing Starting Material, Reagent Or Products
Chemistry Class 12 · Chapter 8
8.17 Complete each synthesis by giving missing starting material, reagent or products
📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Arithmetic-Geometric Progression (AGP)
- Year
- 2025
- Shift
- 24 Jan Shift 2
- Q Number
- Q8
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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