SOLUTION: if a,b are positive numbers such that a+b=1 , prove that a^2+b^2 >= 1/2

Question 1016895: if a,b are positive numbers such that a+b=1 , prove that a^2+b^2 >= 1/2
Answer by robertb(5830) (Show Source): You can put this solution on YOUR website!

Now for any quadratic expression , the maximum or minimum value is . In this case, A = 2 >0, and hence we have a minimum value.
The minimum value of is then equal to .
This ends the solution.
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