Given:

   a,b,c >0 and a+b+c=1 ;
   P=(1/a)+(2/b)+(3/c);

1)Find the minimum value of P;
2)Does P have maximum value ?

ok
as we can see
one of the values of the a can be very close to zero

ie .5 .4999....9999 and .000.....00001

1 / .00000001 approaches infinity
leaving the maximum = infinity

minimum =
1/.3333 + 1/.33333 + 1/.3333

= (1/1/3)^3

= 27

2 minutes to solve question
how did i get .333 repeater?
the smallest number when all variable are equal
so 1 = a + b + c
so 1 = 3x
so x = 1/3

i can differentiate if anyone wwants
but thats just a waste of time

Posted by quddous behrouzi on 2002-06-21 10:07:53