Complex numbers - animated definition The letter i - math word definition The letter j - math word definition Imaginary-number Platonic solid Icosahedron - A regular polyhedron with 20 faces - One of the platonic solids Identity Trigonometry identities Complex numbers - animated definition Number Imaginary-number The letter i - math word definition The letter j - math word definition Real-number Calculus - Improper Integrals Triangle Centers Overview Triangle incenter, description and properties How to construct (draw) the incircle of a triangle with compass and straightedge or ruler Triangle incircle definition How to construct the incenter of a triangle with compass and straightedge Incenter of a regular polygon Incenter coordinates of a triangle with calculator (Coordinate Geometry) Incenter How to construct (draw) the incircle of a triangle with compass and straightedge or ruler Triangle incircle definition Incircle of a Polygon How to construct the incenter of a triangle with compass and straightedge Incircle of a triangle Incircle Incenter of a regular polygon Included side definition Included angle definition Included - math word definition Triangle inequality theorem- Math Open Reference Inequality (opposite of equation) Triangle inequality theorem converse Initial side - math word definition - Trigonometry Incircle of a Polygon Inradius Triangle incircle definition Inscribed (cyclic) quadrilateral Area of an inscribed quadrilateral Inscribed - math word definition Square inscribed in a circle Triangle incircle definition Arc Peripheral Angle Angle inscribed in a semicircle Diagonals of an inscribed quadrilateral Parallelogram inscribed in a quadrilateral Inscribed angle of a circle Incircle of a triangle How to construct a regular hexagon inscribed in a circle with compass and straightedge or ruler How to construct an equilateral triangle inscribed in a given circle with compass and straightedge or ruler Constructing a regular pentagon inscribed in a circle How to construct a square inscribed in a circle with compass and straightedge or ruler Calculus - Instantaneous Velocity Integer Number Calculus - Integral Test Calculus - Polar Area Calculus - Functions defined using integrals Calculus - Properties of Definite Integrals Calculus - Improper Integrals Calculus - Riemann Sums Calculus - Integration By Substitution Intercept (b) of a line (Coordinate Geometry) Equation of a line - slope and intercept form. (Coordinate Geometry) Introduction to Lines in Coordinate Geometry Intercepted arc Interior of an angle definition Triangle interior angles definition Interior angles of an inscribed quadrilateral Interior - math word definition Interior / exterior angles of a polygon Alternate Interior Angles definition Interior Angles of a transversal definition Polygon Interior Angles Calculus - Intermediate Value Theorem Intersecting straight lines. (Coordinate Geometry) Intersecting Chord Theorem Intersecting Secant Theorem Intersection - math word definition Intersecting Secant Angles Theorem Number The inverse trigonometry functions Calculus - Invertible Functions Number Irrational number - math word definition Rational Number - math word definition Irregular polygon - math word definition Area of an Irregular Polygon Isosceles triangle - math word definition How to construct (draw) an isosceles triangle given base and altitude with compass and straightedge or ruler How to construct an isosceles triangle given base and one side Calculus - Intermediate Value Theorem