Menu Close

Category: Number Theory

Given-a-1-3-3-2-3-3-3-4-3-100-Find-the-remainder-of-dividing-the-number-by-5-a-2-b-0-c-4-d-1-e-3-

Question Number 119956 by bobhans last updated on 28/Oct/20 $${Given}\:{a}\:=\:\mathrm{1}+\mathrm{3}+\mathrm{3}^{\mathrm{2}} +\mathrm{3}^{\mathrm{3}} +\mathrm{3}^{\mathrm{4}} +…+\mathrm{3}^{\mathrm{100}} \\ $$$${Find}\:{the}\:{remainder}\:{of}\:{dividing}\:{the}\:{number} \\ $$$${by}\:\mathrm{5}\:. \\ $$$$\left({a}\right)\:\mathrm{2}\:\:\:\:\:\left({b}\right)\:\mathrm{0}\:\:\:\:\:\:\:\left({c}\right)\mathrm{4}\:\:\:\:\:\:\left({d}\right)\mathrm{1}\:\:\:\:\:\:\left({e}\right)\:\mathrm{3} \\ $$ Answered by talminator2856791 last…

Let-x-y-z-be-nonnegative-real-numbers-which-satisfy-x-y-z-1-Find-minimum-value-of-Q-2-x-2-y-2-z-

Question Number 119790 by bemath last updated on 27/Oct/20 $${Let}\:{x},{y},{z}\:{be}\:{nonnegative}\:{real} \\ $$$${numbers},\:{which}\:{satisfy}\:{x}+{y}+{z}=\mathrm{1} \\ $$$${Find}\:{minimum}\:{value}\:{of}\: \\ $$$${Q}=\sqrt{\mathrm{2}−{x}}\:+\:\sqrt{\mathrm{2}−{y}}\:+\:\sqrt{\mathrm{2}−{z}}\:. \\ $$ Answered by 1549442205PVT last updated on 27/Oct/20…

Suppose-that-the-greatest-common-divisor-of-the-positive-integers-a-b-and-c-is-1-and-ab-a-b-c-Prove-that-a-b-is-a-perfect-square-

Question Number 119657 by bemath last updated on 26/Oct/20 $${Suppose}\:{that}\:{the}\:{greatest}\:{common}\:{divisor}\:{of} \\ $$$${the}\:{positive}\:{integers}\:{a},{b}\:{and}\:{c}\:{is}\:\mathrm{1}\:{and} \\ $$$$\frac{{ab}}{{a}−{b}}\:=\:{c}\:.\:{Prove}\:{that}\:{a}−{b}\:{is}\:{a} \\ $$$${perfect}\:{square} \\ $$ Commented by som(math1967) last updated on 26/Oct/20…

n-0-1-n-2n-1-1-pi-4-2-pi-2-12-3-pi-8-4-pi-2-6-

Question Number 53620 by kaivan.ahmadi last updated on 23/Jan/19 $$\underset{\mathrm{n}=\mathrm{0}} {\overset{\infty} {\sum}}\:\:\:\frac{\left(−\mathrm{1}\right)^{\mathrm{n}} }{\mathrm{2n}+\mathrm{1}}\:=? \\ $$$$ \\ $$$$\mathrm{1}.\:\frac{\pi}{\mathrm{4}}\:\:\:\:\:\:\:\:\mathrm{2}.\:\frac{\pi^{\mathrm{2}} }{\mathrm{12}}\:\:\:\:\:\mathrm{3}.\:\frac{\pi}{\mathrm{8}}\:\:\:\:\:\mathrm{4}.\:\frac{\pi^{\mathrm{2}} }{\mathrm{6}} \\ $$ Commented by turbo msup…

Let-x-y-Z-if-x-2-y-2-divide-xy-1-then-prove-x-2-y-2-xy-1-is-square-of-integer-number-

Question Number 53618 by kaivan.ahmadi last updated on 23/Jan/19 $$\mathrm{Let}\:\mathrm{x},\mathrm{y}\in\mathbb{Z} \\ $$$$\mathrm{if}\:\mathrm{x}^{\mathrm{2}} +\mathrm{y}^{\mathrm{2}} \:\mathrm{divide}\:\mathrm{xy}+\mathrm{1}\:\mathrm{then}\:\mathrm{prove} \\ $$$$\frac{\mathrm{x}^{\mathrm{2}} +\mathrm{y}^{\mathrm{2}} }{\mathrm{xy}+\mathrm{1}}\:\mathrm{is}\:\mathrm{square}\:\mathrm{of}\:\mathrm{integer}\:\mathrm{number} \\ $$ Commented by mr W last…

8-1-1-2-1-1-2-2-1-1-2-4-1-1-2-8-1-1-2-32-1-2-60-

Question Number 118880 by bemath last updated on 20/Oct/20 $$\mathrm{8}\left(\mathrm{1}+\frac{\mathrm{1}}{\mathrm{2}}\right)\left(\mathrm{1}+\frac{\mathrm{1}}{\mathrm{2}^{\mathrm{2}} }\right)\left(\mathrm{1}+\frac{\mathrm{1}}{\mathrm{2}^{\mathrm{4}} }\right)\left(\mathrm{1}+\frac{\mathrm{1}}{\mathrm{2}^{\mathrm{8}} }\right)…\left(\mathrm{1}+\frac{\mathrm{1}}{\mathrm{2}^{\mathrm{32}} }\right)+\:\frac{\mathrm{1}}{\mathrm{2}^{\mathrm{60}} }=? \\ $$ Answered by Dwaipayan Shikari last updated on 20/Oct/20…

Find-the-natural-number-n-such-n-7-a-17-b-a-N-b-N-and-the-sum-of-all-its-divisors-1-and-n-included-is-2456-

Question Number 183998 by JDamian last updated on 01/Jan/23 $$\mathrm{Find}\:\mathrm{the}\:\mathrm{natural}\:\mathrm{number}\:\boldsymbol{\mathrm{n}}\:{such} \\ $$$$\:\:\:\:\:\:\:{n}=\mathrm{7}^{{a}} \centerdot\mathrm{17}^{{b}} \:\:\:\:\:\:{a}\in\mathbb{N},\:\:\:{b}\in\mathbb{N} \\ $$$$\mathrm{and}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{all}\:\mathrm{its}\:\mathrm{divisors}\:\left(\mathrm{1}\:\mathrm{and}\right. \\ $$$$\left.\boldsymbol{\mathrm{n}}\:\mathrm{included}\right)\:\mathrm{is}\:\mathrm{2456}. \\ $$ Commented by Rasheed.Sindhi last updated…