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Question Number 147419 Answers: 1 Comments: 0

How can we apply Cardano′s method in 2x^3 +5x^2 +x+2 i get u and v are solution of t^2 −56t+6859=0 but i think it′s wrong pls help

$${How}\:{can}\:{we}\:{apply}\:{Cardano}'{s}\:{method}\:{in} \\ $$$$\mathrm{2}{x}^{\mathrm{3}} +\mathrm{5}{x}^{\mathrm{2}} +{x}+\mathrm{2} \\ $$$$ \\ $$$${i}\:{get}\:{u}\:{and}\:{v}\:{are}\:{solution}\:{of}\:{t}^{\mathrm{2}} −\mathrm{56}{t}+\mathrm{6859}=\mathrm{0} \\ $$$${but}\:{i}\:{think}\:{it}'{s}\:{wrong}\:{pls}\:{help} \\ $$

Question Number 147418 Answers: 1 Comments: 0

In an RLC series circuit, R=1kilo ohms,L=0.2H,C=1 F. If the voltage source is given by: (V=150 sin 377t )V. What is the peak current delivered by the source?

$$\mathrm{In}\:\mathrm{an}\:\mathrm{R}{LC}\:\mathrm{series}\:\mathrm{circuit}, \\ $$$$\mathrm{R}=\mathrm{1kilo}\:\mathrm{ohms},\mathrm{L}=\mathrm{0}.\mathrm{2H},\mathrm{C}=\mathrm{1} \mathrm{F}. \\ $$$$\mathrm{If}\:\mathrm{the}\:\mathrm{voltage}\:\mathrm{source}\:\mathrm{is}\:\mathrm{given}\:\mathrm{by}: \\ $$$$\left(\mathrm{V}=\mathrm{150}\:\mathrm{sin}\:\mathrm{377t}\:\right)\mathrm{V}.\:\mathrm{What}\:\mathrm{is}\:\mathrm{the} \\ $$$$\mathrm{peak}\:\mathrm{current}\:\mathrm{delivered}\:\mathrm{by}\:\mathrm{the}\: \\ $$$$\mathrm{source}? \\ $$

Question Number 147417 Answers: 1 Comments: 0

how can find taylor series of f(z)=cot(z) when z=5π

$${how}\:{can}\:{find}\:{taylor}\:{series}\:{of}\:{f}\left({z}\right)={cot}\left({z}\right)\:{when}\:{z}=\mathrm{5}\pi \\ $$

Question Number 147411 Answers: 2 Comments: 0

Question Number 147406 Answers: 1 Comments: 0

find ∫_C ((z+2)/(sin((z/2))))dz ,∣z∣=3π

$${find}\:\int_{{C}} \frac{{z}+\mathrm{2}}{{sin}\left(\frac{{z}}{\mathrm{2}}\right)}{dz}\:\:\:,\mid{z}\mid=\mathrm{3}\pi \\ $$

Question Number 147405 Answers: 1 Comments: 1

detirmine the residues f(z)=((cosz)/(z^2 (z−π)^3 ))

$${detirmine}\:{the}\:{residues}\:{f}\left({z}\right)=\frac{{cosz}}{{z}^{\mathrm{2}} \left({z}−\pi\right)^{\mathrm{3}} } \\ $$

Question Number 147404 Answers: 1 Comments: 1

find taylor series of f(z)=cotz ,z=5π

$${find}\:{taylor}\:{series}\:{of}\:{f}\left({z}\right)={cotz}\:,{z}=\mathrm{5}\pi \\ $$

Question Number 147402 Answers: 2 Comments: 0

f(x+1)(x+2)....(x+2018) f′(0)=?

$$\boldsymbol{{f}}\left(\boldsymbol{{x}}+\mathrm{1}\right)\left(\boldsymbol{{x}}+\mathrm{2}\right)....\left(\boldsymbol{{x}}+\mathrm{2018}\right) \\ $$$$\boldsymbol{{f}}'\left(\mathrm{0}\right)=? \\ $$

Question Number 147399 Answers: 0 Comments: 0

∫_0 ^(π/2) (e^(2arctg(u)) /( (√u)))

$$\int_{\mathrm{0}} ^{\frac{\pi}{\mathrm{2}}} \frac{{e}^{\mathrm{2}{arctg}\left({u}\right)} }{\:\sqrt{{u}}} \\ $$

Question Number 147397 Answers: 1 Comments: 0

hmmmm ! 11×11=4 22×22=16 33×33=?

$$\boldsymbol{\mathrm{hmmmm}}\:! \\ $$$$\mathrm{11}×\mathrm{11}=\mathrm{4} \\ $$$$\mathrm{22}×\mathrm{22}=\mathrm{16} \\ $$$$\mathrm{33}×\mathrm{33}=? \\ $$

Question Number 147396 Answers: 0 Comments: 0

Question Number 147381 Answers: 1 Comments: 0

On pose H_n (α)=Π_(k=1) ^(n−1) sin((α/(2n))+((kπ)/n)) a) montrer que ∀α≠0, 2^(n−1) H_n (α)=((sin((α/2)))/(sin((α/(2n))))) b) Calculer lim_(α→0) H_n (α) c) De^ duire que ∀α≥2, sin((π/n))×sin(((2π)/n))×....×sin((((n−1)π)/n))=(π/2^(n−1) )..

$${On}\:{pose}\:{H}_{{n}} \left(\alpha\right)=\underset{{k}=\mathrm{1}} {\overset{{n}−\mathrm{1}} {\prod}}{sin}\left(\frac{\alpha}{\mathrm{2}{n}}+\frac{{k}\pi}{{n}}\right) \\ $$$$\left.{a}\right)\:{montrer}\:{que}\:\forall\alpha\neq\mathrm{0},\: \\ $$$$\mathrm{2}^{{n}−\mathrm{1}} {H}_{{n}} \left(\alpha\right)=\frac{{sin}\left(\frac{\alpha}{\mathrm{2}}\right)}{{sin}\left(\frac{\alpha}{\mathrm{2}{n}}\right)} \\ $$$$\left.{b}\right)\:{Calculer}\:{lim}_{\alpha\rightarrow\mathrm{0}} \:{H}_{{n}} \left(\alpha\right) \\ $$$$\left.{c}\right)\:{D}\acute {{e}duire}\:{que}\:\forall\alpha\geqslant\mathrm{2},\: \\ $$$${sin}\left(\frac{\pi}{{n}}\right)×{sin}\left(\frac{\mathrm{2}\pi}{{n}}\right)×....×{sin}\left(\frac{\left({n}−\mathrm{1}\right)\pi}{{n}}\right)=\frac{\pi}{\mathrm{2}^{{n}−\mathrm{1}} }.. \\ $$

Question Number 147413 Answers: 0 Comments: 0

An experiment consist of flipping a coin and then flipping it a second time if a head occurs.If a tail appears on thei first flip then a die is tossed once. a. Listthe element of the sample space S.b b. List the element of S corresponding to the event A that a number less than 4 occurred on the die. c. List thet element of S corresponding to the event B that 2 tails occurred.

$$ \\ $$$$\mathrm{An}\:\mathrm{experiment}\:\mathrm{consist}\:\mathrm{of}\:\mathrm{flipping}\:\mathrm{a} \\ $$$$\mathrm{coin}\:\mathrm{and}\:\mathrm{then}\:\mathrm{flipping}\:\mathrm{it}\:\mathrm{a}\:\mathrm{second}\:\mathrm{time}\: \\ $$$$\mathrm{if}\:\mathrm{a}\:\mathrm{head}\:\mathrm{occurs}.\mathrm{If}\:\mathrm{a}\:\mathrm{tail}\:\mathrm{appears}\:\mathrm{on}\:\mathrm{thei} \\ $$$$\mathrm{first}\:\mathrm{flip}\:\mathrm{then}\:\mathrm{a}\:\mathrm{die}\:\mathrm{is}\:\mathrm{tossed}\:\mathrm{once}.\: \\ $$$$\mathrm{a}.\:\mathrm{Listthe}\:\mathrm{element}\:\mathrm{of}\:\mathrm{the}\:\mathrm{sample}\:\mathrm{space}\:\mathrm{S}.\mathrm{b} \\ $$$$\mathrm{b}.\:\mathrm{List}\:\mathrm{the}\:\mathrm{element}\:\mathrm{of}\:\mathrm{S}\:\mathrm{corresponding} \\ $$$$\mathrm{to}\:\mathrm{the}\:\mathrm{event}\:\mathrm{A}\:\mathrm{that}\:\mathrm{a}\:\mathrm{number}\:\mathrm{less}\:\mathrm{than}\: \\ $$$$\mathrm{4}\:\mathrm{occurred}\:\mathrm{on}\:\mathrm{the}\:\mathrm{die}.\: \\ $$$$\mathrm{c}.\:\mathrm{List}\:\mathrm{thet}\:\mathrm{element}\:\mathrm{of}\:\mathrm{S}\:\mathrm{corresponding}\:\mathrm{to}\:\mathrm{the}\: \\ $$$$\mathrm{event}\:\mathrm{B}\:\mathrm{that}\:\mathrm{2}\:\mathrm{tails}\:\mathrm{occurred}. \\ $$

Question Number 147412 Answers: 1 Comments: 0