Math Help - min value

1. min value

what is the min value of

(a + b)/(1/a + 1/b)

i) given a, b are both +ve
ii) no restriction on a, b

2. Originally Posted by itsmaximhere
what is the min value of

(a + b)/(1/a + 1/b)

i) given a, b are both +ve
ii) no restriction on a, b

$\frac{a+b}{\frac{1}{a} + \frac{1}{b}} = \frac{a+b}{\frac{a+b}{ab}} =( a+b) \times \frac{ab}{a+b} = ab$

Hope that helps.