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Category: Limits

consider-the-function-f-x-1-2x-2-if-x-is-rational-1-x-4-if-x-is-irrational-Use-the-sandwich-pinchin-theorem-to-prove-that-lim-x-0-f-x-1-

Question Number 75930 by Rio Michael last updated on 21/Dec/19 $${consider}\:{the}\:{function} \\ $$$$\:{f}\left({x}\right)\:=\:\begin{cases}{\mathrm{1}+\mathrm{2}{x}^{\mathrm{2}} ,\:{if}\:{x}\:{is}\:{rational}}\\{\mathrm{1}\:+\:{x}^{\mathrm{4}} ,\:{if}\:{x}\:{is}\:{irrational}}\end{cases} \\ $$$${Use}\:{the}\:{sandwich}\left({pinchin}\right)\:{theorem}\:{to} \\ $$$${prove}\:{that}\:\underset{{x}\rightarrow\mathrm{0}} {\mathrm{lim}}\:{f}\left({x}\right)\:=\:\mathrm{1}. \\ $$ Terms of Service…

lim-x-x-2-x-3-x-x-3-1-1-7-cos-1-x-

Question Number 141463 by bramlexs22 last updated on 19/May/21 $$\:\:\:\:\underset{{x}\rightarrow\infty} {\mathrm{lim}}\:{x}^{\mathrm{2}} \left(\:\sqrt[{\mathrm{7}\:\:}]{\frac{{x}^{\mathrm{3}} +{x}}{{x}^{\mathrm{3}} +\mathrm{1}}}\:−\mathrm{cos}\:\frac{\mathrm{1}}{{x}}\right)? \\ $$ Commented by jcarlos last updated on 19/May/21 $$\:\:\:\:\underset{{x}\rightarrow\infty} {\mathrm{lim}}\:{x}^{\mathrm{2}}…

lim-x-pi-4-x-pi-4-sin-3x-3-pi-4-2-1-sin2x-

Question Number 10374 by ridwan balatif last updated on 06/Feb/17 $$\underset{{x}\rightarrow\frac{\pi}{\mathrm{4}}} {\mathrm{lim}}\frac{\left(\mathrm{x}−\frac{\pi}{\mathrm{4}}\right)\mathrm{sin}\left(\mathrm{3x}−\mathrm{3}\frac{\pi}{\mathrm{4}}\right)}{\mathrm{2}\left(\mathrm{1}−\mathrm{sin2x}\right)}=…? \\ $$ Answered by mrW1 last updated on 06/Feb/17 $${let}\:{u}={x}−\frac{\pi}{\mathrm{4}} \\ $$$${with}\:{x}\rightarrow\frac{\pi}{\mathrm{4}},\:{u}\rightarrow\mathrm{0} \\…

prove-that-lim-x-x-1-x-1-

Question Number 75694 by malwaan last updated on 15/Dec/19 $$\boldsymbol{{prove}}\:\boldsymbol{{that}}\: \\ $$$$\underset{\boldsymbol{{x}}\rightarrow\infty} {\boldsymbol{{lim}}}\:\boldsymbol{{x}}^{\frac{\mathrm{1}}{\boldsymbol{{x}}}} \:=\mathrm{1} \\ $$ Answered by vishalbhardwaj last updated on 15/Dec/19 $$\left({as}\:{x}\rightarrow\infty\:\mathrm{then}\:\frac{\mathrm{1}}{{x}}\:\rightarrow\:\mathrm{0}\right) \\…

Prove-that-if-lim-x-a-f-1-x-L-1-and-lim-x-a-f-2-x-L-2-then-lim-x-a-f-1-x-f-2-x-L-1-L-2-

Question Number 10094 by Tawakalitu ayo mi last updated on 23/Jan/17 $$\mathrm{Prove}\:\mathrm{that}\:\mathrm{if}\:\:\:\underset{{x}\rightarrow\mathrm{a}} {\mathrm{lim}}\:\:\mathrm{f}_{\mathrm{1}} \left(\mathrm{x}\right)\:=\:\mathrm{L}_{\mathrm{1}} \:\:\mathrm{and}\:\: \\ $$$$\underset{{x}\rightarrow\mathrm{a}} {\mathrm{lim}}\:\:\:\mathrm{f}_{\mathrm{2}} \left(\mathrm{x}\right)\:=\:\mathrm{L}_{\mathrm{2}} \:\mathrm{then}\:\underset{{x}\rightarrow\mathrm{a}} {\mathrm{lim}}\:\left[\mathrm{f}_{\mathrm{1}} \left(\mathrm{x}\right)+\mathrm{f}_{\mathrm{2}} \left(\mathrm{x}\right)\right]\:=\:\mathrm{L}_{\mathrm{1}} +\mathrm{L}_{\mathrm{2}} \\…