Question and Answers Forum

All Questions   Topic List

AllQuestion and Answers: Page 1144

Question Number 102169    Answers: 5   Comments: 0

∫_0 ^1 x^(3/2) (√(1−x)) dx ?

$$\underset{\mathrm{0}} {\overset{\mathrm{1}} {\int}}{x}^{\mathrm{3}/\mathrm{2}} \:\sqrt{\mathrm{1}−{x}}\:{dx}\:? \\ $$

Question Number 102165    Answers: 2   Comments: 0

calculate ∫_(−∞) ^∞ ((x^2 dx)/((x^2 −x+1)^3 ))

$$\mathrm{calculate}\:\int_{−\infty} ^{\infty} \:\:\frac{\mathrm{x}^{\mathrm{2}} \mathrm{dx}}{\left(\mathrm{x}^{\mathrm{2}} −\mathrm{x}+\mathrm{1}\right)^{\mathrm{3}} } \\ $$

Question Number 102164    Answers: 1   Comments: 0

solve y^(′′) −y^′ +3y = e^(−x) sin(2x)

$$\mathrm{solve}\:\mathrm{y}^{''} \:−\mathrm{y}^{'} \:\:+\mathrm{3y}\:=\:\mathrm{e}^{−\mathrm{x}} \mathrm{sin}\left(\mathrm{2x}\right) \\ $$

Question Number 102163    Answers: 1   Comments: 0

solve y^(′′) −2xy^′ =xe^(−x^2 )

$$\mathrm{solve}\:\:\mathrm{y}^{''} \:−\mathrm{2xy}^{'} \:\:=\mathrm{xe}^{−\mathrm{x}^{\mathrm{2}} } \\ $$

Question Number 102162    Answers: 0   Comments: 0

let f(x) =arctan((2/(x+1))) 1)find f^((n)) (x) and f^((n)) (0) 2)developp f at integer serie

$$\mathrm{let}\:\mathrm{f}\left(\mathrm{x}\right)\:=\mathrm{arctan}\left(\frac{\mathrm{2}}{\mathrm{x}+\mathrm{1}}\right) \\ $$$$\left.\mathrm{1}\right)\mathrm{find}\:\mathrm{f}^{\left(\mathrm{n}\right)} \left(\mathrm{x}\right)\:\mathrm{and}\:\mathrm{f}^{\left(\mathrm{n}\right)} \left(\mathrm{0}\right) \\ $$$$\left.\mathrm{2}\right)\mathrm{developp}\:\mathrm{f}\:\mathrm{at}\:\mathrm{integer}\:\mathrm{serie} \\ $$

Question Number 102161    Answers: 0   Comments: 0

find ∫ ((x(√(x−1))−(x−1)(√x))/((x+1)(√x)−x(√(x+1)))) dx

$$\mathrm{find}\:\int\:\frac{\mathrm{x}\sqrt{\mathrm{x}−\mathrm{1}}−\left(\mathrm{x}−\mathrm{1}\right)\sqrt{\mathrm{x}}}{\left(\mathrm{x}+\mathrm{1}\right)\sqrt{\mathrm{x}}−\mathrm{x}\sqrt{\mathrm{x}+\mathrm{1}}}\:\mathrm{dx} \\ $$

Question Number 102160    Answers: 0   Comments: 0

1) let a<1 calculate ∫_0 ^π ((cosθdθ)/((a^2 −2acosθ +1)^2 )) 2) find the value of ∫_0 ^π ((cosθ)/((4−2(√3)cosθ)^2 ))dθ

$$\left.\mathrm{1}\right)\:\mathrm{let}\:\mathrm{a}<\mathrm{1}\:\mathrm{calculate}\:\int_{\mathrm{0}} ^{\pi} \:\frac{\mathrm{cos}\theta\mathrm{d}\theta}{\left(\mathrm{a}^{\mathrm{2}} −\mathrm{2acos}\theta\:+\mathrm{1}\right)^{\mathrm{2}} } \\ $$$$\left.\mathrm{2}\right)\:\mathrm{find}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\:\int_{\mathrm{0}} ^{\pi} \:\:\frac{\mathrm{cos}\theta}{\left(\mathrm{4}−\mathrm{2}\sqrt{\mathrm{3}}\mathrm{cos}\theta\right)^{\mathrm{2}} }\mathrm{d}\theta \\ $$$$ \\ $$

Question Number 102158    Answers: 1   Comments: 0

calculate ∫_(−∞) ^(+∞) (dx/((x^2 +1)^2 (x^2 +9)^2 ))

$$\mathrm{calculate}\:\int_{−\infty} ^{+\infty} \:\frac{\mathrm{dx}}{\left(\mathrm{x}^{\mathrm{2}} \:+\mathrm{1}\right)^{\mathrm{2}} \left(\mathrm{x}^{\mathrm{2}} \:+\mathrm{9}\right)^{\mathrm{2}} } \\ $$

Question Number 102159    Answers: 0   Comments: 0

calculate ∫_(−∞) ^(+∞) (dx/((x^2 −x+3)^2 ( 2x^2 +5)))

$$\mathrm{calculate}\:\int_{−\infty} ^{+\infty} \:\frac{\mathrm{dx}}{\left(\mathrm{x}^{\mathrm{2}} −\mathrm{x}+\mathrm{3}\right)^{\mathrm{2}} \left(\:\mathrm{2x}^{\mathrm{2}} \:+\mathrm{5}\right)} \\ $$

Question Number 105285    Answers: 1   Comments: 2

simplify ((sin θ)/(1+cot θ)) + ((cos θ)/(1+ tan θ)) ?

$${simplify}\:\frac{\mathrm{sin}\:\theta}{\mathrm{1}+\mathrm{cot}\:\theta}\:+\:\frac{\mathrm{cos}\:\theta}{\mathrm{1}+\:\mathrm{tan}\:\theta}\:? \\ $$

Question Number 102146    Answers: 0   Comments: 14

I decided it′s time to leave for a while. I need some peace and calm, I′m losing my zenter... I′ll put more time and energy into my music. I guess I′ll be back; until then, kindest regards & thanks for the teachings!

$$\mathrm{I}\:\mathrm{decided}\:\mathrm{it}'\mathrm{s}\:\mathrm{time}\:\mathrm{to}\:\mathrm{leave}\:\mathrm{for}\:\mathrm{a}\:\mathrm{while}.\:\mathrm{I}\:\mathrm{need} \\ $$$$\mathrm{some}\:\mathrm{peace}\:\mathrm{and}\:\mathrm{calm},\:\mathrm{I}'\mathrm{m}\:\mathrm{losing}\:\mathrm{my}\:{zen}\mathrm{ter}... \\ $$$$\mathrm{I}'\mathrm{ll}\:\mathrm{put}\:\mathrm{more}\:\mathrm{time}\:\mathrm{and}\:\mathrm{energy}\:\mathrm{into}\:\mathrm{my}\:\mathrm{music}. \\ $$$$\mathrm{I}\:\mathrm{guess}\:\mathrm{I}'\mathrm{ll}\:\mathrm{be}\:\mathrm{back};\:\mathrm{until}\:\mathrm{then}, \\ $$$$\mathrm{kindest}\:\mathrm{regards}\:\&\:\mathrm{thanks}\:\mathrm{for}\:\mathrm{the}\:\mathrm{teachings}! \\ $$

Question Number 105283    Answers: 3   Comments: 0

(1) (dy/dx) = ((2xy)/(4x^2 −y^3 )) (2) (dy/dx) = ((sin x+cos x)/(y(2ln y + 1)))

$$\left(\mathrm{1}\right)\:\frac{{dy}}{{dx}}\:=\:\frac{\mathrm{2}{xy}}{\mathrm{4}{x}^{\mathrm{2}} −{y}^{\mathrm{3}} } \\ $$$$\left(\mathrm{2}\right)\:\frac{{dy}}{{dx}}\:=\:\frac{\mathrm{sin}\:{x}+\mathrm{cos}\:{x}}{{y}\left(\mathrm{2ln}\:{y}\:+\:\mathrm{1}\right)} \\ $$

Question Number 102142    Answers: 0   Comments: 0

A four-sidex dice with numbered 1, 2, 3, and 4 is thrown and the number at the base is read. The dice is biased such that the probabilies P_1 , P_2 , P_3 , and P_4 to obtain 1, 2, 3, and 4 respectively are in an arithmetic progression. 1\ Given P_4 =0.4, calculate P_1 , P_2 , and P_3 . 2\ The dice is thrown n-times (n≥1). The throws are assumed to be independent, 2 by 2, and identical. Given U_n -the probability of obtaining for the first time the fourth-n^(th) throw; a\Express U_n in terms of n= b\Given S_n =Σ_(i=1) ^n U_i i. Express Sn in terms of n, and find its limit. ii. Determine the smallest natural number such that S_n >0.999

$$\mathrm{A}\:\mathrm{four}-\mathrm{sidex}\:\mathrm{dice}\:\mathrm{with}\:\mathrm{numbered}\:\mathrm{1},\:\mathrm{2},\:\mathrm{3},\:\mathrm{and}\:\mathrm{4}\:\mathrm{is}\:\mathrm{thrown} \\ $$$$\mathrm{and}\:\mathrm{the}\:\mathrm{number}\:\mathrm{at}\:\mathrm{the}\:\mathrm{base}\:\mathrm{is}\:\mathrm{read}. \\ $$$$\mathrm{The}\:\mathrm{dice}\:\mathrm{is}\:\mathrm{biased}\:\mathrm{such}\:\mathrm{that}\:\mathrm{the}\:\mathrm{probabilies}\:\mathrm{P}_{\mathrm{1}} ,\:\mathrm{P}_{\mathrm{2}} ,\:\mathrm{P}_{\mathrm{3}} , \\ $$$$\mathrm{and}\:\mathrm{P}_{\mathrm{4}} \:\mathrm{to}\:\mathrm{obtain}\:\mathrm{1},\:\mathrm{2},\:\mathrm{3},\:\mathrm{and}\:\mathrm{4}\:\mathrm{respectively}\:\mathrm{are}\:\mathrm{in}\:\mathrm{an} \\ $$$$\mathrm{arithmetic}\:\mathrm{progression}. \\ $$$$\mathrm{1}\backslash\:\mathrm{Given}\:\mathrm{P}_{\mathrm{4}} =\mathrm{0}.\mathrm{4},\:\mathrm{calculate}\:\mathrm{P}_{\mathrm{1}} ,\:\mathrm{P}_{\mathrm{2}} ,\:\mathrm{and}\:\mathrm{P}_{\mathrm{3}} . \\ $$$$\mathrm{2}\backslash\:\mathrm{The}\:\mathrm{dice}\:\mathrm{is}\:\mathrm{thrown}\:\mathrm{n}-\mathrm{times}\:\left(\mathrm{n}\geqslant\mathrm{1}\right).\:\mathrm{The}\:\mathrm{throws}\:\mathrm{are}\:\mathrm{assumed} \\ $$$$\mathrm{to}\:\mathrm{be}\:\mathrm{independent},\:\mathrm{2}\:\mathrm{by}\:\mathrm{2},\:\mathrm{and}\:\mathrm{identical}.\:\mathrm{Given}\:\mathrm{U}_{\mathrm{n}} -\mathrm{the}\:\mathrm{probability} \\ $$$$\mathrm{of}\:\mathrm{obtaining}\:\mathrm{for}\:\mathrm{the}\:\mathrm{first}\:\mathrm{time}\:\mathrm{the}\:\mathrm{fourth}-\mathrm{n}^{\mathrm{th}} \mathrm{throw}; \\ $$$$\mathrm{a}\backslash\mathrm{Express}\:\mathrm{U}_{\mathrm{n}} \:\mathrm{in}\:\mathrm{terms}\:\mathrm{of}\:\mathrm{n}= \\ $$$$\mathrm{b}\backslash\mathrm{Given}\:\mathrm{S}_{\mathrm{n}} =\underset{\mathrm{i}=\mathrm{1}} {\overset{\mathrm{n}} {\sum}}\mathrm{U}_{\mathrm{i}} \\ $$$$\:\:\mathrm{i}.\:\mathrm{Express}\:\mathrm{Sn}\:\mathrm{in}\:\mathrm{terms}\:\mathrm{of}\:\mathrm{n},\:\mathrm{and}\:\mathrm{find}\:\mathrm{its}\:\mathrm{limit}. \\ $$$$\:\mathrm{ii}.\:\mathrm{Determine}\:\mathrm{the}\:\mathrm{smallest}\:\mathrm{natural}\:\mathrm{number}\:\mathrm{such}\:\mathrm{that} \\ $$$$\:\:\:\:\:\:\mathrm{S}_{\mathrm{n}} >\mathrm{0}.\mathrm{999} \\ $$

Question Number 102139    Answers: 1   Comments: 1

We have 4 boys and 2 girls. we choose at random and simultaneous 2 boys and 1 girl to for a group. 1) How many possibilities do we have?

$${We}\:{have}\:\mathrm{4}\:{boys}\:{and}\:\mathrm{2}\:{girls}.\:{we} \\ $$$${choose}\:{at}\:{random}\:{and}\:{simultaneous} \\ $$$$\mathrm{2}\:{boys}\:{and}\:\mathrm{1}\:{girl}\:{to}\:{for}\:{a}\:{group}. \\ $$$$\left.\mathrm{1}\right)\:{How}\:{many}\:{possibilities}\:{do}\:{we}\:{have}? \\ $$

Question Number 102138    Answers: 0   Comments: 0

∫_0 ^1 ∫_(√y) ^0 (√(x^3 +1+ax^2 +bx+c)) dx dy

$$\int_{\mathrm{0}} ^{\mathrm{1}} \int_{\sqrt{{y}}} ^{\mathrm{0}} \sqrt{{x}^{\mathrm{3}} +\mathrm{1}+{ax}^{\mathrm{2}} +{bx}+{c}}\:\:{dx}\:{dy} \\ $$

Question Number 102196    Answers: 0   Comments: 0

ABCD is a square with center O. AB=5 cm. EFGH is a square such as AE=BF=CG=DH. 1) Show with Chasles rules that EF^(→) .FG^(→) =0^→ 2) Determinate the area of EBFO according to the area of ABCD.

$${ABCD}\:{is}\:{a}\:{square}\:{with}\:{center}\:{O}. \\ $$$${AB}=\mathrm{5}\:{cm}. \\ $$$${EFGH}\:{is}\:{a}\:{square}\:{such}\:{as}\: \\ $$$${AE}={BF}={CG}={DH}. \\ $$$$\left.\mathrm{1}\right)\:{Show}\:{with}\:{Chasles}\:{rules}\:{that} \\ $$$$\overset{\rightarrow} {{EF}}.\overset{\rightarrow} {{FG}}=\overset{\rightarrow} {\mathrm{0}} \\ $$$$\left.\mathrm{2}\right)\:{Determinate}\:{the}\:{area}\:{of}\:{EBFO} \\ $$$${according}\:{to}\:{the}\:{area}\:{of}\:{ABCD}. \\ $$

Question Number 102128    Answers: 4   Comments: 0

∫((x+1)/((√x) +1))dx=?

$$\:\int\frac{{x}+\mathrm{1}}{\sqrt{{x}}\:+\mathrm{1}}{dx}=? \\ $$

Question Number 102121    Answers: 3   Comments: 1

∫_(−∞) ^∞ ((sin(x+(π/2)))/(1+x^2 )) dx By real analysis

$$\int_{−\infty} ^{\infty} \frac{{sin}\left({x}+\frac{\pi}{\mathrm{2}}\right)}{\mathrm{1}+{x}^{\mathrm{2}} }\:{dx}\:\:{By}\:{real}\:{analysis} \\ $$

Question Number 102115    Answers: 3   Comments: 3

Γ(s)ζ(s)=∫_0 ^∞ (x^(s−1) /(e^x +1))dx (Prove that) And prove 1+2+3+4+5+6+7+....∞=−(1/(12))

$$\Gamma\left({s}\right)\zeta\left({s}\right)=\int_{\mathrm{0}} ^{\infty} \frac{{x}^{{s}−\mathrm{1}} }{{e}^{{x}} +\mathrm{1}}{dx}\:\:\left({Prove}\:{that}\right) \\ $$$${And}\:{prove}\:\mathrm{1}+\mathrm{2}+\mathrm{3}+\mathrm{4}+\mathrm{5}+\mathrm{6}+\mathrm{7}+....\infty=−\frac{\mathrm{1}}{\mathrm{12}} \\ $$$$ \\ $$

Question Number 102127    Answers: 1   Comments: 0

∫_0 ^2 (1−x^2 )^3 dx=? and write the furmollah

$$\int_{\mathrm{0}} ^{\mathrm{2}} \left(\mathrm{1}−{x}^{\mathrm{2}} \right)^{\mathrm{3}} {dx}=? \\ $$$$\:{and}\:{write}\:{the}\:{furmollah} \\ $$

Question Number 102109    Answers: 0   Comments: 0

Question Number 102101    Answers: 1   Comments: 1

We have 2 red and 1 black tokens. We want to dispose them on 9 places of this checker−board. 1)What the number of possibilities to dispose these 3 tokens on these 9 places. 2)What it is the number of possibilities to dispose these 3 tokens like that: a) one red token on one black place. b)two red tokens on black places. c)zero red token one black places.

$${We}\:{have}\:\mathrm{2}\:{red}\:{and}\:\mathrm{1}\:{black}\:{tokens}. \\ $$$${We}\:{want}\:{to}\:{dispose}\:{them}\:{on}\:\mathrm{9}\:{places} \\ $$$${of}\:{this}\:{checker}−{board}. \\ $$$$\left.\mathrm{1}\right){What}\:{the}\:{number}\:{of}\:{possibilities}\: \\ $$$${to}\:{dispose}\:{these}\:\mathrm{3}\:{tokens}\:{on}\:{these} \\ $$$$\mathrm{9}\:{places}. \\ $$$$\left.\mathrm{2}\right){What}\:{it}\:{is}\:{the}\:{number}\:{of}\:{possibilities} \\ $$$${to}\:{dispose}\:{these}\:\mathrm{3}\:{tokens}\:\:{like}\:{that}: \\ $$$$\left.{a}\right)\:{one}\:{red}\:{token}\:{on}\:{one}\:{black}\:{place}. \\ $$$$\left.{b}\right){two}\:{red}\:{tokens}\:{on}\:{black}\:{places}. \\ $$$$\left.{c}\right){zero}\:{red}\:{token}\:{one}\:{black}\:{places}. \\ $$$$ \\ $$

Question Number 102099    Answers: 1   Comments: 0

∫sinx ∙ cosx ∙cos2x ∙ cos4x dx=?

$$\int{sinx}\:\centerdot\:{cosx}\:\centerdot{cos}\mathrm{2}{x}\:\centerdot\:{cos}\mathrm{4}{x}\:{dx}=? \\ $$

Question Number 102097    Answers: 0   Comments: 2

∫((cos^2 x −cos^2 x)/(cosx−cosx))dx=?

$$\int\frac{{cos}^{\mathrm{2}} {x}\:−{cos}^{\mathrm{2}} {x}}{{cosx}−{cosx}}{dx}=? \\ $$

Question Number 102096    Answers: 0   Comments: 8

Question Number 102094    Answers: 0   Comments: 5

good evenig for all this is an answerd question i will repost it if: f(x)=(√(x−2)) is there a cirtical point when x=2 ?

$${good}\:{evenig}\:{for}\:{all} \\ $$$$ \\ $$$${this}\:{is}\:{an}\:{answerd}\:{question}\:{i}\:{will}\:{repost}\:{it} \\ $$$${if}: \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:{f}\left({x}\right)=\sqrt{{x}−\mathrm{2}} \\ $$$${is}\:{there}\:{a}\:{cirtical}\:{point}\:{when}\:{x}=\mathrm{2}\:? \\ $$$$ \\ $$$$ \\ $$$$ \\ $$$$ \\ $$

  Pg 1139      Pg 1140      Pg 1141      Pg 1142      Pg 1143      Pg 1144      Pg 1145      Pg 1146      Pg 1147      Pg 1148   

Terms of Service

Privacy Policy

Contact: info@tinkutara.com