Q55.The coefficient of x7 in the expression (1 + x)10 + x(1 + x)9 + x2(1 + x)8+. . . . +x10 , is (1) 210 (2) 330 (3) 120 (4) 420
What This Question Tests
This problem tests the ability to recognize a mixed series, split it into two arithmetic progressions, and calculate their sum to find the total sum.
Concepts Tested
Formulas Used
S_n = n/2(2a + (n-1)d)
📚 NCERT Sections This Tests
5.12 — Write All The Geometrical Isomers Of [Pt(Nh3)(Br)(Cl)(Py)] And How Many Of
Chemistry Class 11 · Chapter 5
5.12 Write all the geometrical isomers of [Pt(NH3)(Br)(Cl)(py)] and how many of these will exhibit optical isomers?
5.11 — Draw All The Isomers (Geometrical And Optical) Of:
Chemistry Class 11 · Chapter 5
5.11 Draw all the isomers (geometrical and optical) of: (i) [CoCl2(en)2] + (ii) [Co(NH3)Cl(en)2] 2+ (iii) [Co(NH3)2Cl2(en)]+
2.2 — A Regular Hexagon Of Side 10 Cm Has A Charge 5 Mc At Each Of Its
Physics Class 11 · Chapter 2
2.2 A regular hexagon of side 10 cm has a charge 5 mC at each of its vertices. Calculate the potential at the centre of the hexagon.
📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Arithmetic-Geometric Progression
- Year
- 2020
- Shift
- 07 Jan Shift 2
- Q Number
- Q55
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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