to.] HIK HTRAK.III //.VJf 



wlu algebraic sign of VA* + JP in to be ohoten to 



a> t. in.tK. - positive, ince l always pod- 



v A* + jfr 



t#n of V w to IH opposite to 



that of tho mimlHT represented by C. 



lU'noe, to reduce et|u.iti"n < 1 > t< th.- imnnal i'..rrn. i.r., to 

 tin- t'.'im ..f equation (4). it i> .i,ly necessary to dixide equa- 

 lion V^4 f -f ^*, with tlu- si k ni |.r..jM-rly ebosen, and 



transpose the constant term t> th.- -.-. .-h-l member. This 



(4) AnofAer m*-' f he normal form. 



.-ijuatinn w4x -f- By+ C0 and xcoao -f y sino = /> 

 represent the same lint-, ili.-n they must have tbe same 

 ,y- intercept and the same slope, t.0., 



*- 



B sin a 



.1 



* B 



Squaring eq. (6), and adding 1 to each member, gives 



At + Bi^cofa 



B* MH- a 



1 



sin* a* 



.*. sin a = 



oosa-- l and t>- "" 



^ 



