For negative x both functions oscillate and approach 0 as x→-∞. For positive x the function Ai(x) monotonically decays towards zero and the function Bi(x) approaches ∞.
The values of x where Ai(x)=0 (all at x<0) can't be expressed in a simple form, so we label them αn, where α1≅-2.34 is the first one, α2≅-4.09 is the second one, and so on. Similarly, the zeroes of Bi(x) are β1≅-1.17, β2≅-3.27, and so on.
The derivatives of the Airy functions look similar.
We can label the zeroes of the derivatives in the same way: α'1≅-1.02, β'n≅-2.29, and so on.