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**2.**A surface formed by the rotation of a catenary.**4.**A number that is added to another number**8.**The centre of a circle which goes through all vertices of a polygon.**9.**A six-sided polygon.**11.**A value under which a whole number of tenths of data fall.**13.**A measure of angle which is the ratio of the arc length to the radius formed by a circular arc with the angle.**14.**An equivalence relation indicating two mathematical sentences to be necessary and sufficient conditon of each other.**16.**A branch of mathematics, the study of (infinitely many) infinitesimalquantities (which may be changing).**17.**A polynomial with two terms.**18.**A plane figure with 2 right angles.**19.**An SI derived unit of radioacitivity denoted by the symbol Bq.**20.**A line segment between two vertices in a graph (graph theory) or geometric shape..**21.**An informal name for symbol ∩, used to denote intersection of sets that is easier to say than the polysyllabic "intersection".**22.**A particular unit within a set of units of the same type. (e.g. CMwithin the set of units for lengths.)**24.**The locus of a point on the circumference of a circle rolling inside of another circle.**25.**Rewriting a mathematical expression in an equivalent form that is considered to be longer or more complicated**27.**A method of inference which attempts to "justify" conclusions by applying rules of inference on the premises of the argument and other such conclusions.**28.**A type of discontinuity, where the hole is a point whose inclusion into the curve would make the curve continuous.**29.**1. A unit of angle, commonly representing one-ninetieth of a right angle.**30.**The condition of an expression of 2 variables that is linear while considering individually each variable (while the other variable is fixed.)

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**1.**An unproven (but also not disproven) assertion considered/assumed/proposed to be true.**3.**A controlled process for making observations and gathering data.**5.**The process of splitting a mathematical object into two or more objects of the same type, such as fractions, functions or matrices.**6.**Also known as indefinite integration**7.**The symbol representing an nth root,.**10.**A beam or such similar structures which is anchored at only one end such that it resists rotation under load.**12.**A measure of how little an approximation deviates from the true value**15.**Also known as extraction, the process of finding a root of a number. The opposite process is called involution.**23.**The segment of the perpendicular bisector of a side of a regular polygon that runs between the centre and the side.**26.**The deviation from being perfectly circular.