# convex angle

A positive angle is   if it is at most 180 , i.e. $\pi$ radians.  Cf. the convex set.

A convex angle $\alpha$ is

• straight  if  $\alpha=180^{\mathrm{o}}$,

• obtuse  if  $90^{\mathrm{o}}<\alpha<180^{\mathrm{o}}$,

• right  if  $\alpha=90^{\mathrm{o}}$,

• acute  if  $0^{\mathrm{o}}<\alpha<90^{\mathrm{o}}$,

• skew  if it is acute or obtuse.

Note.  The angle between two curves (http://planetmath.org/ConformalMapping) which intersect each other in a point $P$ means the angle between the tangent lines of the curves in $P$; such an angle may always be chosen acute or right.

 Title convex angle Canonical name ConvexAngle Date of creation 2013-03-22 14:48:07 Last modified on 2013-03-22 14:48:07 Owner pahio (2872) Last modified by pahio (2872) Numerical id 17 Author pahio (2872) Entry type Definition Classification msc 51M04 Related topic Quadrant  Related topic SolidAngle Related topic OrthogonalCurves Related topic ComplementaryAngles Related topic ContourLine Defines straight angle Defines obtuse angle  Defines right angle Defines acute angle Defines straight Defines obtuse Defines right Defines acute