HP Prime Graphing NW280AAABA manual Center, Divisionpoint, Element, Inter

center

Returns the center of a circle.

center(circle)

Example: center(circle(x2+y2–x–y)) gives point(1/2,1/2)

division_point

For two points A and B, and a numerical factor k, returns a point C such that C-B=k*(C-A).

division_point(point1, point2, realk)

Example: division_point(0,6+6*i,4) returns point

(8,8)

element

Creates a point on a geometric object whose abscissa is a given value or creates a real value on a given interval.

element(object, real) or element(real1..real2)

Examples:

element(plotfunc(x2),–2) creates a point on the graph of y = x2. Initially, this point will appear at (–2,4). You can move the point, but it will always remain on the graph of its function.

element(0..5) creates a value of 2.5 initially. Tapping on this value and pressing Eenables you to press >and

<to increase or decrease the value in a manner similar to a slider bar. Press Eagain to close the slider bar. The value you set can be used as a coefficient in a function you subsequently plot.

inter

Returns the intersections of two curves as a vector.

inter(curve1, curve2)

Example: inter	⎛	8	x2	x	⎞	returns
	⎝		– ----, --		– 1
			6	2	⎠

that there are two intersections:

•(6,2)

6	2
–9	–11
	--------
	2

. This indicates

•(–9,–5.5)

166 Geometry