diff --git a/src/sage/interfaces/maxima_abstract.py b/src/sage/interfaces/maxima_abstract.py
index 961c20aaac..3d601d8939 100644
--- a/src/sage/interfaces/maxima_abstract.py
+++ b/src/sage/interfaces/maxima_abstract.py
@@ -1743,7 +1743,7 @@ class MaximaAbstractElement(ExtraTabCompletion, InterfaceElement):
             sage: y,d = var('y,d')
             sage: f = function('f')
             sage: latex(maxima(derivative(f(x*y), x)))
-            \left(\left.{{{\it \partial}}\over{{\it \partial}\,  {\it t_0}}}\,f\left({\it t_0}\right)  \right|_{{\it t_0}={\it x}\,  {\it y}}\right)\,{\it y}
+            \left(\left.{{{\it \partial}}\over{{\it \partial}\,  {\it t}_{0}}}\,f\left({\it t}_{0}\right)  \right|_{{\it t}_{0}={\it x}\,  {\it y}}\right)\,{\it y}
             sage: latex(maxima(derivative(f(x,y,d), d,x,x,y)))
             {{{\it \partial}^4}\over{{\it \partial}\,{\it d}\,  {\it \partial}\,{\it x}^2\,{\it \partial}\,  {\it y}}}\,f\left({\it x} ,  {\it y} , {\it d}\right)
             sage: latex(maxima(d/(d-2)))
diff --git a/src/sage/manifolds/differentiable/metric.py b/src/sage/manifolds/differentiable/metric.py
index 3cd6ad3235..1e18af1a6b 100644
--- a/src/sage/manifolds/differentiable/metric.py
+++ b/src/sage/manifolds/differentiable/metric.py
@@ -993,7 +993,7 @@ class PseudoRiemannianMetric(TensorField):
              2-dimensional differentiable manifold S^2
             sage: g.riemann()[:]
             [[[[0, 0], [0, 0]], [[0, sin(th)^2], [-sin(th)^2, 0]]],
-             [[[0, (cos(th)^2 - 1)/sin(th)^2], [1, 0]], [[0, 0], [0, 0]]]]
+             [[[0, -1], [1, 0]], [[0, 0], [0, 0]]]]
 
         In dimension 2, the Riemann tensor can be expressed entirely in terms of
         the Ricci scalar `r`:
diff --git a/src/sage/symbolic/expression.pyx b/src/sage/symbolic/expression.pyx
index dfb8751467..27402e54ab 100644
--- a/src/sage/symbolic/expression.pyx
+++ b/src/sage/symbolic/expression.pyx
@@ -7154,7 +7154,7 @@ cdef class Expression(CommutativeRingElement):
             sage: ex = lcm(sin(x)^2 - 1, sin(x)^2 + sin(x)); ex
             (sin(x)^2 + sin(x))*(sin(x)^2 - 1)/(sin(x) + 1)
             sage: ex.simplify_full()
-            -cos(x)^2*sin(x)
+            sin(x)^3 - sin(x)
 
         TESTS:
 
@@ -10004,7 +10004,7 @@ cdef class Expression(CommutativeRingElement):
 
             sage: f=tan(3*x)
             sage: f.simplify_trig()
-            (4*cos(x)^2 - 1)*sin(x)/(4*cos(x)^3 - 3*cos(x))
+            -(4*cos(x)^2 - 1)*sin(x)/(4*cos(x)*sin(x)^2 - cos(x))
             sage: f.simplify_trig(False)
             sin(3*x)/cos(3*x)