doc fixes, and extended Basic Linear Algebra and Reductions sections

Eigen/Array

@@ -11,7 +11,7 @@ namespace Eigen {
   * (accessible from MatrixBase::cwise()), including:
   *  - matrix-scalar sum,
   *  - coeff-wise comparison operators,
-  *  - sin, cos, sqrt, pow, exp, log, square, cube, reciprocal.
+  *  - sin, cos, sqrt, pow, exp, log, square, cube, inverse (reciprocal).
   *
   * This module also provides various MatrixBase methods, including:
   *  - \ref MatrixBase::all() "all", \ref MatrixBase::any() "any",

Eigen/src/Core/MapBase.h

@@ -64,7 +64,7 @@ template<typename Derived> class MapBase
 
     inline int stride() const { return derived().stride(); }
 
-    /** \Returns an expression equivalent to \c *this but having the \c PacketAccess constant
+    /** \returns an expression equivalent to \c *this but having the \c PacketAccess constant
       * set to \c ForceAligned. Must be reimplemented by the derived class. */
     AlignedDerivedType forceAligned() { return derived().forceAligned(); }
 

Eigen/src/Geometry/OrthoMethods.h

@@ -96,7 +96,7 @@ struct ei_someOrthogonal_selector<Derived,2>
 /** \returns an orthogonal vector of \c *this
   *
   * The size of \c *this must be at least 2. If the size is exactly 2,
-  * then the returned vector is a counter clock wise rotation of \c *this, \ie (-y,x).
+  * then the returned vector is a counter clock wise rotation of \c *this, i.e., (-y,x).
   *
   * \sa cross()
   */