Question Number 152715 by Tawa11 last updated on 31/Aug/21
$$\mathrm{By}\:\mathrm{eliminating}\:\:\theta,\:\:\:\mathrm{show}\:\mathrm{that}\:\:\:\:\:\mathrm{x}^{\mathrm{2}} \:\:\:=\:\:\:−\:\:\:\mathrm{y}^{\mathrm{2}} ,\:\:\:\:\:\: \\ $$$$\mathrm{if}\:\:\:\:\:\mathrm{x}\:\mathrm{sin}^{\mathrm{3}} \theta\:\:\:+\:\:\:\mathrm{y}\:\mathrm{cos}^{\mathrm{3}} \theta\:\:\:\:=\:\:\:\:\mathrm{sin}\theta\:\:\:\:\:\:\:\:\:\:\:\:\mathrm{and}\:\:\:\:\:\:\:\:\mathrm{x}\:\mathrm{sin}\theta\:\:\:\:−\:\:\:\mathrm{y}\:\mathrm{cos}\theta\:\:\:\:=\:\:\:\:\mathrm{0} \\ $$
Commented by Tawa11 last updated on 02/Sep/21
$$\mathrm{Thanks}\:\mathrm{sir}.\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you} \\ $$
Commented by mr W last updated on 01/Sep/21
$${question}\:{is}\:{clearly}\:{wrong}. \\ $$$${x}^{\mathrm{2}} =−{y}^{\mathrm{2}} \:{means}\:{simply}\:{x}={y}=\mathrm{0}. \\ $$