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Category: Arithmetic

Question-43350

Question Number 43350 by peter frank last updated on 10/Sep/18 Commented by maxmathsup by imad last updated on 10/Sep/18 $${let}\:\:{S}\:\left({x}\right)={x}\:+\mathrm{2}{x}^{\mathrm{2}} \:+\mathrm{3}{x}^{\mathrm{3}} \:+…{nx}^{{n}} \:\Rightarrow\:\frac{{S}\left({x}\right)}{{x}}=\mathrm{1}+\mathrm{2}{x}\:+\mathrm{3}{x}^{\mathrm{2}} \:+….{nx}^{{n}−\mathrm{1}} \:{but}…

Bobhans-1-Let-n-be-a-positive-integer-and-let-x-and-y-be-positive-real-number-such-that-x-n-y-n-1-Prove-that-k-1-n-1-x-2k-1-x-4k-k-1-n-1-y-2k-1-

Question Number 108818 by bobhans last updated on 19/Aug/20 $$\:\:\frac{\boldsymbol{\mathcal{B}}{ob}\boldsymbol{{hans}}}{\Delta} \\ $$$$\left(\mathrm{1}\right){Let}\:{n}\:{be}\:{a}\:{positive}\:{integer},\:{and}\:{let}\:{x}\:{and}\:{y}\:{be}\:{positive}\:{real}\: \\ $$$${number}\:{such}\:{that}\:{x}^{{n}} \:+\:{y}^{{n}} \:=\:\mathrm{1}\:.\:{Prove}\:{that}\: \\ $$$$\left(\underset{{k}\:=\:\mathrm{1}} {\overset{{n}} {\sum}}\frac{\mathrm{1}+{x}^{\mathrm{2}{k}} }{\mathrm{1}+{x}^{\mathrm{4}{k}} }\:\right)\left(\underset{{k}\:=\:\mathrm{1}} {\overset{{n}} {\sum}}\frac{\mathrm{1}+{y}^{\mathrm{2}{k}} }{\mathrm{1}+{y}^{\mathrm{4}{k}}…

Question-108679

Question Number 108679 by Rasikh last updated on 18/Aug/20 Answered by Dwaipayan Shikari last updated on 18/Aug/20 $$\sqrt{\mathrm{1}+\mathrm{8}}\:=\mathrm{3} \\ $$$$\sqrt{\mathrm{1}+\mathrm{2}.\mathrm{4}}=\mathrm{3} \\ $$$$\sqrt{\mathrm{1}+\mathrm{2}\sqrt{\mathrm{1}+\mathrm{3}.\mathrm{15}}}=\mathrm{3} \\ $$$$\sqrt{\mathrm{1}+\mathrm{2}\sqrt{\mathrm{1}+\mathrm{3}\sqrt{\mathrm{1}+\mathrm{4}\sqrt{\mathrm{1}+\mathrm{5}}}….}}=\mathrm{3} \\…

Question-108594

Question Number 108594 by Rasikh last updated on 18/Aug/20 Answered by 1549442205PVT last updated on 18/Aug/20 $$\mathrm{From}\:\mathrm{a},\mathrm{b},\mathrm{c}>\mathrm{0}\:\frac{\mathrm{1}}{\mathrm{a}}+\frac{\mathrm{1}}{\mathrm{b}}+\frac{\mathrm{1}}{\mathrm{c}}=\mathrm{1we}\:\mathrm{have} \\ $$$$\mathrm{ab}+\mathrm{bc}+\mathrm{ca}=\mathrm{abc}\left(\mathrm{1}\right).\mathrm{Apply}\:\mathrm{Cauchy}'\mathrm{s}\: \\ $$$$\mathrm{inequality}\:\mathrm{for}\:\mathrm{three}\:\mathrm{positive}\:\mathrm{numbers} \\ $$$$\mathrm{we}\:\mathrm{have}\:: \\ $$$$\mathrm{abc}=\mathrm{ab}+\mathrm{bc}+\mathrm{ca}\geqslant\mathrm{3}\:^{\mathrm{3}}…

Question-43036

Question Number 43036 by Rio Michael last updated on 06/Sep/18 Commented by Rio Michael last updated on 06/Sep/18 $${Find}\:{the}\:{area}\:{of}\:{one}\:{square}\:{of}\:{the}\:{squares}\left(\frac{\mathrm{1}}{\mathrm{4}}\:{of}\:{the}\:{big}\:{square}\right) \\ $$ Answered by $@ty@m last…

Q-How-many-common-three-digit-numbers-are-there-in-the-following-two-sequences-a-n-1-5-9-13-b-m-4-7-10-13-

Question Number 173902 by mnjuly1970 last updated on 20/Jul/22 $$ \\ $$$$\:\:{Q}:\:{How}\:{many}\:{common}\:{three}−{digit}\:{numbers} \\ $$$$\:\:\:\:{are}\:{there}\:{in}\:{the}\:{following} \\ $$$$\:\:\:\:\:{two}\:{sequences}? \\ $$$$\:\:\:\:\:\begin{cases}{\:\:{a}_{{n}} \:=\:\mathrm{1}\:\:,\:\mathrm{5}\:,\:\mathrm{9}\:,\mathrm{13}\:,\:…}\\{\:\:{b}_{\:{m}} \:=\:\mathrm{4}\:,\:\mathrm{7}\:,\:\mathrm{10}\:,\:\mathrm{13}\:,…}\end{cases} \\ $$ Answered by mr…

Simplify-x-y-z-x-1-y-1-z-1-x-1-y-1-z-1-x-y-y-z-z-x-

Question Number 42672 by Tawa1 last updated on 31/Aug/18 $$\mathrm{Simplify}:\:\:\:\left(\mathrm{x}\:+\:\mathrm{y}\:+\:\mathrm{z}\right)\left(\mathrm{x}^{−\mathrm{1}} \:+\:\mathrm{y}^{−\mathrm{1}} \:+\:\mathrm{z}^{−\mathrm{1}} \right)\:=\:\left(\mathrm{x}^{−\mathrm{1}} \:\mathrm{y}^{−\mathrm{1}} \:\mathrm{z}^{−\mathrm{1}} \right)\left(\mathrm{x}\:+\:\mathrm{y}\right)\left(\mathrm{y}\:+\:\mathrm{z}\right)\left(\mathrm{z}\:+\:\mathrm{x}\right) \\ $$ Terms of Service Privacy Policy Contact: info@tinkutara.com

Question-108082

Question Number 108082 by ismoilov last updated on 14/Aug/20 Answered by Her_Majesty last updated on 14/Aug/20 $${x}={tan}^{−\mathrm{1}} {t} \\ $$$$\frac{\left({t}+\mathrm{1}\right)\left({t}−\mathrm{2}\right)}{{t}^{\mathrm{2}} +\mathrm{1}}\geqslant\mathrm{0}\:\Rightarrow\:−\mathrm{1}\leqslant{t}\leqslant\mathrm{2} \\ $$$$\Rightarrow\:{for}\:\mathrm{0}\leqslant{x}<\mathrm{2}\pi \\ $$$$\frac{\pi}{\mathrm{2}}−{tan}^{−\mathrm{1}}…