The Airy function Ai(z) satisfies
dz2d2Ai=zAi(z)
(a) Show that for large positive z, the Airy function has the asymptotic form
Ai(z)∼2πz1/41exp(−32z3/2)
(b) Show that for large negative z (writing z=−∣z∣), the Airy function oscillates as
Ai(−∣z∣)∼π∣z∣1/41sin(32∣z∣3/2+4π)
(c) Use the result of (b) to derive the WKB quantization condition for the gravitational well.