# Mathematics

##### Across
1. 2. A surface formed by the rotation of a catenary.
2. 4. A number that is added to another number
3. 8. The centre of a circle which goes through all vertices of a polygon.
4. 9. A six-sided polygon.
5. 11. A value under which a whole number of tenths of data fall.
6. 13. A measure of angle which is the ratio of the arc length to the radius formed by a circular arc with the angle.
7. 14. An equivalence relation indicating two mathematical sentences to be necessary and sufficient conditon of each other.
8. 16. A branch of mathematics, the study of (infinitely many) infinitesimalquantities (which may be changing).
9. 17. A polynomial with two terms.
10. 18. A plane figure with 2 right angles.
11. 19. An SI derived unit of radioacitivity denoted by the symbol Bq.
12. 20. A line segment between two vertices in a graph (graph theory) or geometric shape..
13. 21. An informal name for symbol ∩, used to denote intersection of sets that is easier to say than the polysyllabic "intersection".
14. 22. A particular unit within a set of units of the same type. (e.g. CMwithin the set of units for lengths.)
15. 24. The locus of a point on the circumference of a circle rolling inside of another circle.
16. 25. Rewriting a mathematical expression in an equivalent form that is considered to be longer or more complicated
17. 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.
18. 28. A type of discontinuity, where the hole is a point whose inclusion into the curve would make the curve continuous.
19. 29. 1. A unit of angle, commonly representing one-ninetieth of a right angle.
20. 30. The condition of an expression of 2 variables that is linear while considering individually each variable (while the other variable is fixed.)
##### Down
1. 1. An unproven (but also not disproven) assertion considered/assumed/proposed to be true.
2. 3. A controlled process for making observations and gathering data.
3. 5. The process of splitting a mathematical object into two or more objects of the same type, such as fractions, functions or matrices.
4. 6. Also known as indefinite integration
5. 7. The symbol representing an nth root,.
6. 10. A beam or such similar structures which is anchored at only one end such that it resists rotation under load.
7. 12. A measure of how little an approximation deviates from the true value
8. 15. Also known as extraction, the process of finding a root of a number. The opposite process is called involution.
9. 23. The segment of the perpendicular bisector of a side of a regular polygon that runs between the centre and the side.
10. 26. The deviation from being perfectly circular.