1. The problem statement, all variables and given/known data What is the relationship between vmax and λmax and why isn't it just vmaxλmax = c 2. Relevant equations vλ = c vmax = 5.88 x 1010T s-1 K-1 λmax = 0.290T-1 cm K 3. The attempt at a solution I worked out that Bλ = -dv/dλ Bv where -dv/dλ = c/λ2 So I thought that λmax = -dv/dλ vmax but that doesn't seem to work. Any idea what I have missed? I have been playing around with various rearrangements for a while . . . do I need to do some more calculus?