[ 300 ] 
ct be perpendicular to the tangent dt, and let the 
ablciffa cp be = « X — . Then will the faid tan- 
* ml 
gent d t he = ms 
mz 
i and the fluxion thereof 
will be found 
, _i . 
•=: \ mn % X 
m 
I rr^ z^ X 
m%Y 
v'«-‘ -j- 2/z — x."" 
In the expreflion 
yqzll. 
-j- by I'" c -\r dy 
n** 
let 
c dy 
a by 
be fuppofed = z. Then will ^ be => and 
the propofed expreflion will be 
u a 
Tc) * - * X z-^k 
az 
— ^ X d — bzV+^- 
Taking, in the lafl; article, r and s each = |, 
% 
^ — , b=ziy and c-=^ti‘, we have 
m 
n , 
— + > 
m 
1 / 1 1 \ 
y'^ y f ni^ n—'^ y~^ y i 
i V *^n^ + 2fy^y^J 
X « — _ _y 
m 
— mnz’~-^z X 
1 2 
m — z‘ 
n* + mzY 
ft 
