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Question Number 58775 Answers: 0 Comments: 0

solve exactly: x^8 −8x^7 −16x^6 +208x^5 −152x^4 −928x^3 +704x^2 +1088x−368=0

$$\mathrm{solve}\:\mathrm{exactly}: \\ $$$${x}^{\mathrm{8}} −\mathrm{8}{x}^{\mathrm{7}} −\mathrm{16}{x}^{\mathrm{6}} +\mathrm{208}{x}^{\mathrm{5}} −\mathrm{152}{x}^{\mathrm{4}} −\mathrm{928}{x}^{\mathrm{3}} +\mathrm{704}{x}^{\mathrm{2}} +\mathrm{1088}{x}−\mathrm{368}=\mathrm{0} \\ $$

Question Number 58774 Answers: 0 Comments: 3

let f(x) =∫_(π/3) ^(π/2) (dθ/(1+xtanθ)) with x real 1) find a explicit form for f(x) 2) determine also g(x) =∫_(π/3) ^(π/2) ((tanθ)/((1+xtanθ)^2 )) dθ 3) let U_n (x) =f^((n)) (x) give U_n (x) at form of integral. 4) calculate ∫_(π/3) ^(π/2) (dθ/(1+2tanθ)) and ∫_(π/3) ^(π/2) ((tanθ dθ)/((1+2tanθ)^2 ))

$${let}\:{f}\left({x}\right)\:=\int_{\frac{\pi}{\mathrm{3}}} ^{\frac{\pi}{\mathrm{2}}} \:\:\frac{{d}\theta}{\mathrm{1}+{xtan}\theta}\:\:\:{with}\:{x}\:{real} \\ $$$$\left.\mathrm{1}\right)\:{find}\:{a}\:{explicit}\:{form}\:{for}\:{f}\left({x}\right) \\ $$$$\left.\mathrm{2}\right)\:{determine}\:{also}\:{g}\left({x}\right)\:=\int_{\frac{\pi}{\mathrm{3}}} ^{\frac{\pi}{\mathrm{2}}} \:\:\:\frac{{tan}\theta}{\left(\mathrm{1}+{xtan}\theta\right)^{\mathrm{2}} }\:{d}\theta \\ $$$$\left.\mathrm{3}\right)\:{let}\:{U}_{{n}} \left({x}\right)\:={f}^{\left({n}\right)} \left({x}\right)\:\:{give}\:{U}_{{n}} \left({x}\right)\:{at}\:{form}\:{of}\:{integral}. \\ $$$$\left.\mathrm{4}\right)\:{calculate}\:\int_{\frac{\pi}{\mathrm{3}}} ^{\frac{\pi}{\mathrm{2}}} \:\:\:\frac{{d}\theta}{\mathrm{1}+\mathrm{2}{tan}\theta}\:\:{and}\:\:\int_{\frac{\pi}{\mathrm{3}}} ^{\frac{\pi}{\mathrm{2}}} \:\:\:\frac{{tan}\theta\:{d}\theta}{\left(\mathrm{1}+\mathrm{2}{tan}\theta\right)^{\mathrm{2}} } \\ $$

Question Number 58772 Answers: 1 Comments: 0

(1/6)×(2/5)

$$\frac{\mathrm{1}}{\mathrm{6}}×\frac{\mathrm{2}}{\mathrm{5}} \\ $$$$ \\ $$

Question Number 58771 Answers: 0 Comments: 0

decompose inside R(x) the fraction F(x) =(1/((x^2 −4)^n ))

$${decompose}\:{inside}\:{R}\left({x}\right)\:{the}\:{fraction} \\ $$$${F}\left({x}\right)\:=\frac{\mathrm{1}}{\left({x}^{\mathrm{2}} −\mathrm{4}\right)^{{n}} } \\ $$

Question Number 58770 Answers: 2 Comments: 1

find the value of integrals I =∫_0 ^∞ (dx/((x^2 +1)^3 )) , J =∫_0 ^∞ (dx/((x^2 +1)^5 ))

$${find}\:{the}\:{value}\:{of}\:{integrals} \\ $$$$\:{I}\:=\int_{\mathrm{0}} ^{\infty} \:\:\:\:\frac{{dx}}{\left({x}^{\mathrm{2}} +\mathrm{1}\right)^{\mathrm{3}} }\:\:\:,\:{J}\:=\int_{\mathrm{0}} ^{\infty} \:\:\:\frac{{dx}}{\left({x}^{\mathrm{2}} \:+\mathrm{1}\right)^{\mathrm{5}} } \\ $$

Question Number 58769 Answers: 0 Comments: 1

decompose the fractions inside C(x) 1) (1/((x^2 +1)^3 )) 2) (1/((x^2 +1)^5 ))