Question Number 131599 by ajfour last updated on 06/Feb/21
![](https://www.tinkutara.com/question/18530.png)
Commented by ajfour last updated on 06/Feb/21
![Find coordinates of P, in terms of a,b, and R.](https://www.tinkutara.com/question/Q131600.png)
$${Find}\:{coordinates}\:{of}\:{P},\:{in}\:{terms} \\ $$$${of}\:{a},{b},\:{and}\:{R}. \\ $$
Answered by mr W last updated on 06/Feb/21
![P(a cos θ, b sin θ) let μ=(b/a), λ=(R/a) tan ϕ=(μ/(tan θ)) R cos ϕ+b sin θ=R ⇒λ((tan θ)/( (√(μ^2 +tan^2 θ))))+μ sin θ=λ ...θ=...](https://www.tinkutara.com/question/Q131615.png)
$${P}\left({a}\:\mathrm{cos}\:\theta,\:{b}\:\mathrm{sin}\:\theta\right) \\ $$$${let}\:\mu=\frac{{b}}{{a}},\:\lambda=\frac{{R}}{{a}} \\ $$$$\mathrm{tan}\:\varphi=\frac{\mu}{\mathrm{tan}\:\theta} \\ $$$${R}\:\mathrm{cos}\:\varphi+{b}\:\mathrm{sin}\:\theta={R} \\ $$$$\Rightarrow\lambda\frac{\mathrm{tan}\:\theta}{\:\sqrt{\mu^{\mathrm{2}} +\mathrm{tan}^{\mathrm{2}} \:\theta}}+\mu\:\mathrm{sin}\:\theta=\lambda \\ $$$$…\theta=… \\ $$