I would like to know if this is the question flat out or if this question arose from another question...

Without loss of generality, we can consider only since the other two expressions are the same but with a=b and a=c, because there is no reason why you can't call the 3 numbers a,b,c in any order when you find them

Now, if we let a approach zero, the expression approaches zero. From what you've said a cannot be 0, but you can let a keep getting smaller and the value of lamda will continue to decrease

For instance, let b=.49998 and c=.49998 and see what happens

Then let b=.4999999998 and c=.4999999998 and see what happens (with a calculator you'll probably get an answer of 0 with round off)