Maxima and MinimaHard
Question
If xy = c2 then the minimum value of ax + by (a > 0, b > 0) is-
Options
A.- c
B.c
C.2c
D.-2c
Solution
xy = c2
min value z = ax + by; a > 0 b > 0
z = ax + b.
= a - 
= a - 
= 0
a =
x = ± c
at x = c
gives minima
z = a × c
c
+ c 
= 2c
min value z = ax + by; a > 0 b > 0
z = ax + b.
= a - = a - = 0a =
x = ± c
at x = c
gives minimaz = a × c
c
+ c = 2cCreate a free account to view solution
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