Merge pull request #16425 from sympy/smichr-patch-3

Update test_simplify.py

sympy/simplify/tests/test_simplify.py

@@ -434,6 +434,15 @@ def test_logcombine_1():
     a = Symbol("a")
     z, w = symbols("z,w", positive=True)
     b = Symbol("b", real=True)
+
+    # a single unknown can combine
+    assert logcombine(log(x) + log(2)) == log(2*x)
+
+    eq = log(abs(x)) + log(abs(y))
+    assert logcombine(eq) == eq
+    reps = {x: 0, y: 0}
+    assert log(abs(x)*abs(y)).subs(reps) != eq.subs(reps)
+
     assert logcombine(log(x) + 2*log(y)) == log(x) + 2*log(y)
     assert logcombine(log(x) + 2*log(y), force=True) == log(x*y**2)
     assert logcombine(a*log(w) + log(z)) == a*log(w) + log(z)

sympy/solvers/tests/test_solvers.py

@@ -705,8 +705,8 @@ def test_issue_4671_4463_4467():
     #assert solve((2**exp(y**2/x) + 2)/(x**2 + 15), y) == [-sqrt(x*log(1 + I*pi/log(2)))
     #                                                    , sqrt(x*log(1 + I*pi/log(2)))]
     assert solve((2**exp(y**2/x) + 2)/(x**2 + 15), y) == [
-         sqrt(x*(-log(log(2)) + log(log(2) + I*pi))),
-        -sqrt(-x*(log(log(2)) - log(log(2) + I*pi)))]
+         sqrt(x*(log((log(2) + I*pi)/log(2)))),
+        -sqrt(-x*(log((log(2) + I*pi)/log(2))))]
 
     C1, C2 = symbols('C1 C2')
     f = Function('f')