diff --git a/ps12-2.py b/ps12-2.py
index e4991e5..3d959e7 100644
--- a/ps12-2.py
+++ b/ps12-2.py
@@ -35,8 +35,21 @@ for i in range(4):
 print("==================")
 print("Expectation Values")
 print("==================")
-for psi in psi_funcs:
-    pass  # TODO
+expect_xs = []
+for i, psi in enumerate(psi_funcs):
+    expect_x = np.sum(np.conjugate(psi) * x_vals * psi)
+    expect_xs.append(expect_x)
+    print(f'expect_x_{i} = {expect_x}')
+
+expect_x_sqrds = []
+for i, psi in enumerate(psi_funcs):
+    expect_x_sqrd = np.sum(np.conjugate(psi) * x_vals ** 2 * psi)
+    expect_x_sqrds.append(expect_x_sqrd)
+    print(f'expect_x_{i} = {expect_x_sqrd}')
+
+for i, psi in enumerate(psi_funcs):
+    sigma_x = np.sqrt(expect_x_sqrds[i] - expect_xs[i] ** 2)
+    print(f'sigma_x_{i} = {sigma_x}')
 
 pl.rcParams['figure.dpi'] = 300
 fig, axs = pl.subplots(2, 2, tight_layout=True)