Question Number 169148 by mathlove last updated on 25/Apr/22
$$\underset{{x}\rightarrow\pi} {\mathrm{lim}}\frac{\pi{cos}\mathrm{2}{x}−\mathrm{1}}{\mathrm{1}+{cosx}}=? \\ $$
Commented by infinityaction last updated on 25/Apr/22
$$\:\:\:\:\:{p}\:=\:\:\:\frac{\pi\mathrm{cos}\:\mathrm{2}\pi−\mathrm{1}}{\mathrm{1}+\mathrm{cos}\:\pi} \\ $$$$\:\:\:\:\:\:{p}\:\:=\:\:\frac{\pi×\mathrm{1}−\mathrm{1}}{\mathrm{1}−\mathrm{1}}\:=\:\frac{\pi−\mathrm{1}}{\mathrm{0}}\:=\:\infty \\ $$$$ \\ $$
Commented by mathlove last updated on 25/Apr/22
$${way}\:\pi{cos}\mathrm{2}{x}−\mathrm{1}\neq\pi\left({cos}\mathrm{2}{x}−\mathrm{1}\right) \\ $$