Fr.: triangles congrus
Two triangles when all corresponding sides and interior angles have the same measure. The triangles will have the same shape and size, but one may be a mirror image of the other.
sebar-e sé-pahlu-barâbar (#)
Fr.: triangle équilatéral
A triangle having three equal sides.
sebar-e do-pahlu-barâbar (#)
Fr.: triangle équilatéral
A triangle having two sides equal.
From L.L. isosceles, from Gk. isoskeles "with equal legs; that can be divided into two equal parts," from isos "equal, identical," → iso-, + skelos "leg."
Fr.: triangle de Pascal
An array of numbers in the shape of a triangle, having a 1 at the top and also at the ends of each row. Each number is obtained by summing the two adjacent numbers to it in the preceding row. Each row is a set of → binomial coefficients. In the expansion of (x + y)n, the coefficients of x and y are given by the n-th row of Pascal's traingle.
Fr.: triangle de Reuleaux
A shape of constant width created using an equilateral triangle and three similar circles. The equilateral triangle lies in the first circle with a vertex coinciding with the center of the circle and the sides equal to the circle radius. The centers of the two other circles are located at the two other vertices. The Reuleaux triangle is the intersection of the three circles.
Named after Franz Reuleaux (1829-1905), a German engineer, specialist of analysis and design of mechines; → triangle.
sebar-e râst (#)
Fr.: triangle droit
A triangle one of whose angles is a → right angle.
Fr.: triangle scalène
A triangle no two sides of which are equal.
From L.L. scalenus, from Gk. skalenos "uneven, unequal, rough," from skallein "chop, hoe," related to skolios "crooked," from PIE base *(s)qel- "crooked, curved, bent;" → triangle.
Sebar, → triangle; nâjur-pahlu "dissimilar sides," from nâjur "dissimilar, ill-matched" + pahlu "side, flank" (Mid.Pers. pahlug "side, rib," Av. pərəsu- "rib," Ossetic fars "side, flank," cf. Skt. párśu- "rib," Lith. piršys (pl.) "horse breast").
Fr.: triangle sphérique
A triangle drawn on the → surface of a → sphere. A spherical triangle, like a plane triangle, may be right, obtuse, acute, equilateral, isosceles, or scalene. The sum of the angles of a spherical triangle is greater than 180° (π) and less than 540° (3π). See also → spherical excess.
Fr.: triangle d'été
sebar (#), seguš (#)
Sebar "three-sided," from sé, → three, +
+ bar "side; breadth; breast,"
variant var (Mid.Pers. var "breast;"
Av. vouru "wide, broad, extended" (vourucašāni- "looking far"),
related to varah- "breast;" cf. Skt. urú- "wide, broad,"
úras- "breast;" Gk. eurus "wide, broad;"
PIE base uer-, ueru-s"wide, broad").
Fr.: inégalité triangulaire