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S To calculate the focus and length of latus rectum [G-SLV]-[FOCS]/[LEN]
Example To determine the focus and length of latus rectum for the parabola X =
(Y – 2)
2
+ 3
Use the following V-Window settings.
Xmin = –1, Xmax = 10, Xscale = 1
Ymin = –5, Ymax = 5, Yscale = 1
K CONICS
U
@UAUBU(DRAW)
(G-SLV)
(FOCS)
(Calculates the focus.)
(G-SLV)
(LEN)
(Calculates the length of latus rectum.)
• When calculating two foci for an ellipse or hyperbolic graph, press C to calculate the
second focus. Pressing B returns to the first focus.
• When calculating two vertexes for a hyperbolic graph, press C to calculate the second
vertex. Pressing B returns to the first vertex.
• Pressing C when calculating the vertices of an ellipse will calculate the next value.
Pressing B will scroll back through previous values. An ellipse has four vertices.
S To calculate the center [G-SLV]-[CNTR]
Example To determine the center for the circle
(X + 2)
2
+ (Y + 1)
2
= 2
2
K CONICS
AAAAU
AU@UAU(DRAW)
(G-SLV)
(CNTR)
(Calculates the center.)