CDS Government Jobs Exams Logical Reasoning Blood Relations

If r and s are the real numbers such that r+s=1 and s lies between 0 to 1, then what is the maximum value of product rs ?

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maximum value of rs=.25

rs=r(1-r)=r-r^2
to find point of maximum , take derivative and equate to 0.
2r=1

r=1/2
since r+s=1
s=1/2

max. of product rs=.5*.5=.25
11 years agoHelpfull: Yes(14) No(1)

1/4 by taking the derivative of the given function
11 years agoHelpfull: Yes(2) No(0)

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