Question Number 72248 by Omer Alattas last updated on 26/Oct/19
Commented by Omer Alattas last updated on 26/Oct/19
$${solv}\:{to}\:{x}\: \\ $$
Answered by MJS last updated on 26/Oct/19
$$\mathrm{tan}^{\mathrm{2}} \:{x}\:−\mathrm{2sin}\:\mathrm{2}{x}\:=\mathrm{0} \\ $$$${x}=\mathrm{arctan}\:{t} \\ $$$${t}^{\mathrm{2}} −\mathrm{2}\frac{\mathrm{2}{t}}{{t}^{\mathrm{2}} +\mathrm{1}}=\mathrm{0} \\ $$$$\frac{{t}^{\mathrm{2}} \left({t}^{\mathrm{2}} +\mathrm{1}\right)−\mathrm{4}{t}}{{t}^{\mathrm{2}} +\mathrm{1}}=\mathrm{0} \\ $$$${t}\left({t}^{\mathrm{3}} +{t}−\mathrm{4}\right)=\mathrm{0} \\ $$$${t}_{\mathrm{1}} =\mathrm{0} \\ $$$${t}_{\mathrm{2}} \approx\mathrm{1}.\mathrm{37880} \\ $$$${t}_{\mathrm{3},\:\mathrm{4}} \approx−.\mathrm{689398}\pm\mathrm{1}.\mathrm{55750i} \\ $$$${x}_{\mathrm{1}} ={n}\pi \\ $$$${x}_{\mathrm{2}} \approx.\mathrm{943311}+{n}\pi \\ $$
Commented by Omer Alattas last updated on 27/Oct/19
$${thank}\:{you}\:{pro} \\ $$
Commented by Omer Alattas last updated on 26/Oct/19
$${how}\:{i}\:{can}\:{write}\:{the}\:{anccer}\:{in}\:{rad}\:{pleas} \\ $$
Commented by MJS last updated on 27/Oct/19
$${x}\in\left[\mathrm{0};\:\mathrm{2}\pi\right] \\ $$$${x}_{\mathrm{1}} \:\mathrm{leads}\:\mathrm{to}\:\mathrm{0};\:\pi;\:\mathrm{2}\pi \\ $$$${x}_{\mathrm{2}} \:\mathrm{leads}\:\mathrm{to}\:.\mathrm{943311};\:\mathrm{4}.\mathrm{08490} \\ $$