questionr
Early access
Exams
Joint Entrance Examination
Mathematics
Binomial Theorem
Question 304
Question 304 of 347
Medium
MCQ
The value of r for which 20Cr 20C0 + 20Cr-1 20C1 + 20Cr-2 20C2 + . . . . .+ 20C0 20Cr is maximum, is
A
20
B
15
C
10
D
11
Check answer
Press A-D to select · Enter to check
Solutions · 1
Post your solution
Official solution
Given sum = coefficient of xr in the expansion of (1 + x)20(1 + x)20, Which is equal to 40Cr It is maximum when r = 20
Answer the question to unlock
Previous
Next