$$ \frac{35887+j(1050)}{-2824+j(-17)} \ = \ ? $$
This above number is supposed to be the sprung mass response factor to road input at frequency of 6.91 radians/second for the front suspension of a 1958 Jaguar XK150S as per the equation given in Prof. Gillespie's "Fundamentals of Vehicle Dynamics" (1992 Edition) on page 150. I get the answer of "12.70" which is about 4 times the correct answer of "3.16" (as determined by an equation for the same factor as given in Prof. Dukkipati's "Road Vehicle Dynamics"). The question is "what does the above complex number ratio equal?" (am I evaluating it wrong?)...
Brian Paul Wiegand, PE
Take two complex numbers $z_1=a+bi$ and $z_2=c+di$. To compute $\frac{z_1}{z_2}$ note that
$$\frac{a+bi}{c+di}=\frac{(a+bi)\cdot\overline{c+di}}{(c+di)\cdot\overline{c+di}}=\frac{(a+bi)\cdot(c-di)}{(c+di)\cdot(c-di)}=\frac{(ac+bd)+i(bc-ad)}{c^2+d^2}$$
Thus
$$\frac{35887+j(1050)}{-2824+j(-17)}=\frac{(35887\cdot(-2824)+1050\cdot(-17))+j(1050\cdot(-2824)-35887\cdot(-17))}{2824^2+17^2}\approx-12.709-j(0.295)$$
I confirmed this answer with Wolfram Alpha. Perhaps there is an error with the listed correct answer.