PROPERTIES of the CIRCLE. 49 
As the cofine of oom , B is the cofine of 3 
8 
° 
cofine of 5 'X — , and fo on; and when 2—T is a multiple of 
2 by an even number, the laft of the terms A, B, C, &c. is the 
ly 
cofine of “—3 3 DT ; and 4, the firft of the terms a, 4, c, &c. 
i] 
is the cofine of sty pBe ; 6, the fecond, is the cofine of 
a5 x a +; ¢, the third, is the cofine of a x 80 band 
the laft of the terms a, 5, Cy &e. is the cofine of I x nay 
180 
or of m—2 X But when #2—1 is a multiple of 2 by 
an odd number, the laft of the terms A, B, CG &c. is the cofine 
a2—1.., 180° 
of x —'s the ‘firft of the terms 4, b, &c. is the cofine 
of “73 x Jot and the laft of the terms 4, 4, &c. is the co- 
Bror Univerfally, if m be any odd number 
fine of n—2 X 
lefs_ than 2, we have A” + B” + (C” + &c. to out terms, 
Stat Doe ne 
‘terms, = when 7—1I is 
— a bolle aX to — 
a + mole of 2 by an even number; and A” -+ B”-+ C"+ &c., 
3 terms, = —, when 
ae ) 
to terms, — an — 3” — &e.'to 2 
Vor, VIL—P. Te er 2—1 
