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Question Number 164609 Answers: 1 Comments: 0

en posant x=t−(1/t) ∫^(+oo) _0 ((1+t^2 )/(1+t^4 ))dt

$${en}\:{posant}\:{x}={t}−\frac{\mathrm{1}}{{t}} \\ $$$$\underset{\mathrm{0}} {\int}^{+{oo}} \frac{\mathrm{1}+{t}^{\mathrm{2}} }{\mathrm{1}+{t}^{\mathrm{4}} }{dt} \\ $$

Question Number 164606 Answers: 2 Comments: 0

Min f(x)= cos 2x +(√3) sin 2x −2(√3) cos x−2sin x is ...

$$\:{Min}\:{f}\left({x}\right)=\:\mathrm{cos}\:\mathrm{2}{x}\:+\sqrt{\mathrm{3}}\:\mathrm{sin}\:\mathrm{2}{x}\:−\mathrm{2}\sqrt{\mathrm{3}}\:\mathrm{cos}\:{x}−\mathrm{2sin}\:{x} \\ $$$$\:{is}\:... \\ $$

Question Number 164605 Answers: 1 Comments: 0

Question Number 164600 Answers: 3 Comments: 0

Question Number 164599 Answers: 0 Comments: 1

180<θ<270 and 2sinθ−cos θ=0 faind volue of sin θ×cos θ=?

$$\mathrm{180}<\theta<\mathrm{270}\:\:\:\:{and} \\ $$$$\mathrm{2}{sin}\theta−\mathrm{cos}\:\theta=\mathrm{0} \\ $$$${faind}\:\:\:{volue}\:{of} \\ $$$$\mathrm{sin}\:\theta×\mathrm{cos}\:\theta=? \\ $$

Question Number 164598 Answers: 0 Comments: 0

Prove that; ∫_(−∞) ^∞ y tan x + y^3 tan x dx = undefined

$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\boldsymbol{\mathrm{Prove}}\:\boldsymbol{\mathrm{that}}; \\ $$$$\:\:\:\:\:\:\int_{−\infty} ^{\infty} \:\boldsymbol{{y}}\:\boldsymbol{{tan}}\:\boldsymbol{{x}}\:+\:\boldsymbol{{y}}^{\mathrm{3}} \:\:\boldsymbol{{tan}}\:\:\boldsymbol{{x}}\:\boldsymbol{{dx}}\:=\:\boldsymbol{{undefined}} \\ $$

Question Number 164591 Answers: 1 Comments: 0

pour quelle valeur α la serie converge Σ_(n=2) (ln(n)+αln(n−(1/n))

$${pour}\:{quelle}\:{valeur}\:\alpha\:{la}\:{serie}\:{converge} \\ $$$$\underset{{n}=\mathrm{2}} {\sum}\left({ln}\left({n}\right)+\alpha{ln}\left({n}−\frac{\mathrm{1}}{{n}}\right)\right. \\ $$

Question Number 164590 Answers: 1 Comments: 0

∫ ((In(x^2 .e^(cos2) ))/x) dx

$$\int\:\frac{\mathrm{In}\left(\mathrm{x}^{\mathrm{2}} .\boldsymbol{{e}}^{\boldsymbol{{cos}}\mathrm{2}} \right)}{\boldsymbol{\mathrm{x}}}\:\boldsymbol{\mathrm{dx}} \\ $$

Question Number 164589 Answers: 0 Comments: 0

∫ A.^5 (√(x^3 )) dx

$$\int\:\mathrm{A}.\:^{\mathrm{5}} \sqrt{\boldsymbol{\mathrm{x}}^{\mathrm{3}} \:\:}\:\boldsymbol{\mathrm{dx}} \\ $$

Question Number 164588 Answers: 0 Comments: 0

soit K un corps; pour toute permutation σ de S_n , on note P(σ) sa matrice dans la base canonique de K^n . montrer que deux permutations σ_1 et σ_2 sont conjugues dans S_n si et seulement si P(σ_1 ) et P(σ_2 ) sont semblables.

$${soit}\:{K}\:{un}\:{corps};\:{pour}\:{toute}\:{permutation} \\ $$$$\sigma\:{de}\:{S}_{{n}} ,\:{on}\:{note}\:{P}\left(\sigma\right)\:{sa}\:{matrice}\:{dans}\:{la}\:{base} \\ $$$${canonique}\:{de}\:{K}^{{n}} . \\ $$$${montrer}\:{que}\:{deux}\:{permutations}\:\sigma_{\mathrm{1}} \:{et}\:\sigma_{\mathrm{2}} \:{sont} \\ $$$${conjugues}\:{dans}\:{S}_{{n}} \:{si}\:{et}\:{seulement}\:{si}\: \\ $$$${P}\left(\sigma_{\mathrm{1}} \right)\:{et}\:{P}\left(\sigma_{\mathrm{2}} \right)\:{sont}\:{semblables}. \\ $$

Question Number 164585 Answers: 2 Comments: 0

I = ∫_0 ^( 1) (( Li_( 2) ( x ))/(1 + x)) dx = ? −−−−−−

$$ \\ $$$$\:\:\:\:\:\:\:\:\:\mathcal{I}\:=\:\int_{\mathrm{0}} ^{\:\mathrm{1}} \frac{\:\mathrm{Li}_{\:\mathrm{2}} \:\left(\:{x}\:\right)}{\mathrm{1}\:+\:{x}}\:{dx}\:=\:? \\ $$$$\:\:\:\:−−−−−−\: \\ $$

Question Number 164576 Answers: 1 Comments: 0

Question Number 164568 Answers: 2 Comments: 0

(1/( (√(2−x)))) > (1/(x−1))

$$\:\:\:\frac{\mathrm{1}}{\:\sqrt{\mathrm{2}−{x}}}\:>\:\frac{\mathrm{1}}{{x}−\mathrm{1}} \\ $$

Question Number 164564 Answers: 0 Comments: 0

when F does not contain y explicity . Find the extremals of ∫_x_1 ^x_2 ((y′^2 )/x^2 )dx

$$ \\ $$$${when}\:{F}\:{does}\:{not}\:{contain}\:{y}\:{explicity}\:.\:{Find}\:{the}\:{extremals}\:{of} \\ $$$$\underset{{x}_{\mathrm{1}} } {\overset{{x}_{\mathrm{2}} } {\int}}\frac{{y}'^{\mathrm{2}} }{{x}^{\mathrm{2}} }{dx} \\ $$

Question Number 164560 Answers: 2 Comments: 1

6 boys and 6 girls go to an exhibition and the cost of ticket is Rs 10.Each girl has a 10 rupees note while each boy has a 20 rupees note. They stand in a queue at the counter and the cashier does not have any money at the begining , then the number of ways of arranging the boys and girls so that no one waits for a change is A) 132 B) 264 C) 132(720)^2 D)264(720)^2

$$\mathrm{6}\:\mathrm{boys}\:\mathrm{and}\:\mathrm{6}\:\mathrm{girls}\:\mathrm{go}\:\mathrm{to}\:\mathrm{an}\:\mathrm{exhibition}\:\mathrm{and}\:\mathrm{the}\:\mathrm{cost} \\ $$$$\mathrm{of}\:\mathrm{ticket}\:\mathrm{is}\:\mathrm{Rs}\:\mathrm{10}.\mathrm{Each}\:\mathrm{girl}\:\mathrm{has}\:\mathrm{a}\:\mathrm{10}\:\mathrm{rupees}\:\mathrm{note} \\ $$$$\mathrm{while}\:\mathrm{each}\:\mathrm{boy}\:\mathrm{has}\:\mathrm{a}\:\mathrm{20}\:\mathrm{rupees}\:\mathrm{note}.\:\mathrm{They}\:\mathrm{stand}\: \\ $$$$\mathrm{in}\:\mathrm{a}\:\mathrm{queue}\:\mathrm{at}\:\mathrm{the}\:\mathrm{counter}\:\mathrm{and}\:\mathrm{the}\:\mathrm{cashier}\:\mathrm{does} \\ $$$$\mathrm{not}\:\mathrm{have}\:\mathrm{any}\:\mathrm{money}\:\mathrm{at}\:\mathrm{the}\:\mathrm{begining}\:,\:\mathrm{then}\:\mathrm{the}\: \\ $$$$\mathrm{number}\:\mathrm{of}\:\mathrm{ways}\:\mathrm{of}\:\mathrm{arranging}\:\mathrm{the}\:\mathrm{boys}\:\mathrm{and}\:\mathrm{girls} \\ $$$$\mathrm{so}\:\mathrm{that}\:\mathrm{no}\:\mathrm{one}\:\mathrm{waits}\:\mathrm{for}\:\mathrm{a}\:\mathrm{change}\:\mathrm{is} \\ $$$$\left.\mathrm{A}\left.\right)\left.\:\left.\mathrm{132}\:\:\:\:\:\mathrm{B}\right)\:\:\:\:\mathrm{264}\:\mathrm{C}\right)\:\:\mathrm{132}\left(\mathrm{720}\right)^{\mathrm{2}} \:\:\:\:\mathrm{D}\right)\mathrm{264}\left(\mathrm{720}\right)^{\mathrm{2}} \\ $$

Question Number 164555 Answers: 2 Comments: 0

prove that ( _( k−1) ^(2k) ) =^? Σ_(r=0) ^(k−1) ( _( r) ^( k) ) (^( ) _( r+1) ^( k) ) −−−−

$$ \\ $$$$\:\:\:{prove}\:\:{that} \\ $$$$\: \\ $$$$\:\:\:\:\:\:\left(\underset{\:{k}−\mathrm{1}} {\overset{\mathrm{2}{k}} {\:}}\:\right)\:\overset{?} {=}\:\underset{{r}=\mathrm{0}} {\overset{{k}−\mathrm{1}} {\sum}}\:\left(\:\underset{\:{r}} {\overset{\:{k}} {\:}}\:\:\:\right)\:\overset{\:\:} {\left(}\underset{\:{r}+\mathrm{1}} {\overset{\:\:{k}} {\:}}\:\right) \\ $$$$\:\:−−−− \\ $$

Question Number 164553 Answers: 3 Comments: 1