Mathematics key terms

Notation such as $a^n$ in which a base is written with an index.

The plural of index.

A statement comparing two values using a symbol such as $<$, $>$, $\le$ or $\ge$.

Symbols used to compare values: $<$ means less than, while $\leq$ means less than or equal to.

A conclusion about a population drawn from information collected from a sample.

A sequence that continues without a final term.

The amount present when the number of elapsed time periods is zero.

The velocity at the start of the time interval being considered.

A value supplied to a function before its rule is applied.

The rate at one particular value of the independent variable; it is represented by the gradient of the tangent to the curve at that point.

A whole number that may be positive, negative or zero; it has no fractional or decimal part.

A point at which a graph crosses or touches an axis.

Money paid for borrowing money, or money earned by allowing a bank or other organisation to use savings.

A percentage used to calculate interest on money saved or borrowed for a stated period.

An angle formed between two sides at a vertex, measured inside a polygon.

An answer left using the symbol $\pi$, rather than replacing $\pi$ with a rounded decimal.

A line where two parts of a composite shape meet; it is not part of the perimeter if it lies inside the finished shape.

Estimating a value within the range of observed data.

The difference between the upper and lower quartiles; it measures the spread of the middle half of the data.

The difference between the upper and lower quartiles, measuring the spread of the middle 50% of the data.

The event containing outcomes that belong to both $A$ and $B$, written $A\cap B$.

The range between a lower bound and an upper bound within which a root is known to lie.

A method that repeatedly tests the midpoint of an interval and retains the half containing a sign change.

A property that remains unchanged after a transformation or combination of transformations.

A property or point that remains unchanged after a transformation or sequence of transformations.

A line that maps onto itself. Its individual points need not all stay fixed, although every point on a mirror line stays fixed under reflection in that line.

A point that finishes in exactly the same position after a transformation or sequence of transformations.

A feature or quantity that remains unchanged under a transformation.

The calculator function $\cos^{-1}$ used to find an angle from its cosine value.

A function that reverses another function, taking an output back to its original input.