638 MJLESWOBTH’S POCKET-BOOK
A* Major axis Parabola. | Ellipse. Htpbkbola.
B c2 Vb’ + Cc Vb’2 - Cc
a* Minor axis a/c’ A V -g- Vee Co
B Slant height c3 A
a3 Vaj - s’ V A3 + a2
C ; a2
1 Diam. of cone 1 . c
? at vertices j A/a'2B a3
V A
D J Conjugate ( V A2 + a2 - d2 A3 — a2 + d2
d i diameters ( VA2 + <t- - D2 \/ A--a2 + D2
) Distance ot \
F ( foci .. .. J B B
f Focal distance Z/3 4- 4» A —F 2 F- A 2
9 (Distance of) | directrix J f /-(£-/)
G Offset to di tto V gv+f
L Latus rectum V a2 S- A. a2 -T- A.
I Parameter .. d2 4-1)
n Subnormal p’+t y2-t-t y2 -i-t
N 1 Normal .. a/ y2 + n3 Vy- + n'J \/y2 + n2
t Subtangent 2x z Aa z
4z
T 1 Tangent .. Vy2 + p pt + 1- Vy~+T2
V 1 Radius vector ® +f -fy + y2 a/ + y-
(Radius of ) 4 (V v)3 4 \/ (V v)3
1 curvature J A a A a
w (Sine of traced ) 1 angle .. J y*V y-i-v y-~V
( Abscissa from / Ay* A(a±\Za2-4y2) A(o!±Va2 + 4^
a vertex .. f a2 2 a
Ordinate .. a x
y Va ~ \ Ax - x2 A ~ a/x (A + x)
f Distance of y } 1 A | A
( from centre f | • • x 2 '• - + æ i
* In the parabola A ~ height; a = | base.