Q84.If the arithmetic mean and the geometric mean of the pth and qth terms of the sequence −16, 8, −4, 2, … satisfy the equation 4x2 −9x + 5 = 0 , then p + q is equal to _______.
What This Question Tests
This question connects arithmetic mean and geometric mean of terms from a GP with the roots of a quadratic equation, requiring simultaneous equation solving and knowledge of GP formulas.
Concepts Tested
Formulas Used
AM = (a+b)/2
GM = sqrt(ab)
nth term of GP (a*r^(n-1))
Roots of quadratic equation
📚 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.
9.8 — A Beam Of Light Converges At A Point P. Now A Lens Is Placed In The
Physics Class 12 · Chapter 9
9.8 A beam of light converges at a point P. Now a lens is placed in the path of the convergent beam 12cm from P. At what point does the beam converge if the lens is (a) a convex lens of focal length 20cm, and (b) a concave lens of focal length 16cm?
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 Progression (AP) and Geometric Progression (GP)
- Year
- 2021
- Shift
- 26 Feb Shift 2
- Q Number
- Q84
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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