TRACT 1C.
WITHOUT TABLES.
265
a , a a a a* . ,
-p - ip f — =- 4p -1--- - &c : and
n 7 Sr n 1 Sr 480r s ’
a
A = n X (|P- -=«x(V(2-V(l-
S ) - nearly.
rr
4 1
Coral. 7.—And again, since —; x (p — q — \q l =
. , . a . . r a 4p— q
&c ; where q is = —; by subtracting this from --—=
— -q 6 &c, and reducing, there will be obtained A = —- x
tov iUO
{U4P-39q-^)=~x{lU^/2-2V(l-g l ))-S9q-^,
which will commonly give the angle exact to within a minuteof the truth. Where note, that the constant quantity ^ is— *54567409. And from the whole may be drawn the fol-lowing general problem.
PROBLEM.
To perform all the Cases of Trigonometry •without any Tables.
. Having any three, parts of a triangle given, except the threeangles, the other three parts may be found, by some of thefollowing six general theorems.
1 . A = in X {W (2 - V (- nearly. Or
A== f^ x ( 14 v (2 - v(i-i))- S9 T-575) more nearI y-
r 2 r l
_ a a* 3 a i 3.5a 7 3 5.7a 9 .
2. a = n x (—1_I-P-4-&c.)
r ^2.3r> 2.4.5r 5 2.4.6.7r 7 2.4.6.8.9r 9
3. a =
4. r =
VX ^n 2.3« 3 + 2.3.4. 5n s 2.3.4.5 .6.7« 7
&c.)
2.3. 2.3.4.5m s 2.3.4.5.6.7a 7
&C.