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Let |Z(r) - r| le r, for all r = 1,2,3…....

Let `|Z_(r) - r| le r`, for all `r = 1,2,3….,n`. Then `|sum_(r=1)^(n)z_(r)|` is less than

A

n

B

2n

C

n(n+1)

D

`(n(n+1))/(2)`

Text Solution

Verified by Experts

The correct Answer is:
C
`|sum_(r=1)^(n)z_(r)|lesum_(r=1)^(n)|z_(r)|lesum_(r=1)^(n)|z_(r)-r|+sum_(r=1)^(n)rle2sum_(r=1)^(n)r`
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