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Question Number 113354 Answers: 0 Comments: 3

( ((n),(0) )/2)−( ((n),(1) )/3)+( ((n),(2) )/4)−( ((n),(3) )/5)+.....n

$$\frac{\begin{pmatrix}{{n}}\\{\mathrm{0}}\end{pmatrix}}{\mathrm{2}}−\frac{\begin{pmatrix}{{n}}\\{\mathrm{1}}\end{pmatrix}}{\mathrm{3}}+\frac{\begin{pmatrix}{{n}}\\{\mathrm{2}}\end{pmatrix}}{\mathrm{4}}−\frac{\begin{pmatrix}{{n}}\\{\mathrm{3}}\end{pmatrix}}{\mathrm{5}}+.....{n} \\ $$

Question Number 113353 Answers: 1 Comments: 0

What is the maximum number of points to be distributed within a 3×6 to ensure that there are no two points whose distance apart is less than (√2)?

$$\mathrm{What}\:\mathrm{is}\:\mathrm{the}\:\mathrm{maximum}\:\mathrm{number} \\ $$$$\mathrm{of}\:\mathrm{points}\:\mathrm{to}\:\mathrm{be}\:\mathrm{distributed}\:\mathrm{within} \\ $$$$\mathrm{a}\:\mathrm{3}×\mathrm{6}\:\mathrm{to}\:\mathrm{ensure}\:\mathrm{that}\:\mathrm{there}\:\mathrm{are}\:\mathrm{no}\:\mathrm{two} \\ $$$$\mathrm{points}\:\mathrm{whose}\:\mathrm{distance}\:\mathrm{apart}\:\mathrm{is}\:\mathrm{less} \\ $$$$\mathrm{than}\:\sqrt{\mathrm{2}}? \\ $$

Question Number 113346 Answers: 1 Comments: 0

Question Number 113343 Answers: 1 Comments: 1

find the angle between x+3(√(3y))=2,(√(3x))−5y=2 help me sir please

$${find}\:{the}\:{angle}\:{between}\:{x}+\mathrm{3}\sqrt{\mathrm{3}{y}}=\mathrm{2},\sqrt{\mathrm{3}{x}}−\mathrm{5}{y}=\mathrm{2} \\ $$$${help}\:{me}\:{sir}\:{please} \\ $$

Question Number 113341 Answers: 3 Comments: 0

Question Number 113336 Answers: 0 Comments: 0

If 1, a^2 ,a^3 ,...,a^(n−1) are the roots nth of unity , prove that : (1+a)(1+a^2 )(1+a^3 )...(1+a^(n−1) ) = n−2⌊(n/2)⌋

$${If}\:\mathrm{1},\:{a}^{\mathrm{2}} ,{a}^{\mathrm{3}} \:,...,{a}^{{n}−\mathrm{1}} \:{are}\:{the}\:{roots}\: \\ $$$${nth}\:{of}\:{unity}\:,\: \\ $$$${prove}\:{that}\::\:\left(\mathrm{1}+{a}\right)\left(\mathrm{1}+{a}^{\mathrm{2}} \right)\left(\mathrm{1}+{a}^{\mathrm{3}} \right)...\left(\mathrm{1}+{a}^{{n}−\mathrm{1}} \right) \\ $$$$=\:{n}−\mathrm{2}\lfloor\frac{{n}}{\mathrm{2}}\rfloor \\ $$$$ \\ $$

Question Number 113333 Answers: 2 Comments: 0

Question Number 113330 Answers: 1 Comments: 0

Question Number 113323 Answers: 2 Comments: 0

Question Number 113309 Answers: 2 Comments: 4

Question Number 113375 Answers: 0 Comments: 1

(i) How does one find the equation of the perpendicular to a line? (ii) How does one calculate standard deviation. Explain in details.

$$\left(\mathrm{i}\right)\:\mathrm{How}\:\mathrm{does}\:\mathrm{one}\:\mathrm{find}\:\mathrm{the}\:\mathrm{equation}\:\mathrm{of}\:\mathrm{the} \\ $$$$\mathrm{perpendicular}\:\mathrm{to}\:\mathrm{a}\:\mathrm{line}? \\ $$$$ \\ $$$$\left(\mathrm{ii}\right)\:\mathrm{How}\:\mathrm{does}\:\mathrm{one}\:\mathrm{calculate}\:\mathrm{standard} \\ $$$$\mathrm{deviation}.\:\mathrm{Explain}\:\mathrm{in}\:\mathrm{details}. \\ $$

Question Number 113374 Answers: 1 Comments: 5

Find the next term in this sequence: 26,63,124, __

$$\mathrm{Find}\:\mathrm{the}\:\mathrm{next}\:\mathrm{term}\:\mathrm{in}\:\mathrm{this} \\ $$$$\mathrm{sequence}:\:\mathrm{26},\mathrm{63},\mathrm{124},\:\_\_ \\ $$

Question Number 113372 Answers: 1 Comments: 2

2^a +2^b +2^c +2^d =57, find a+b+c+d. a≠b≠c≠d and a,b,c,d are positive integers.

$$\mathrm{2}^{\mathrm{a}} +\mathrm{2}^{\mathrm{b}} +\mathrm{2}^{\mathrm{c}} +\mathrm{2}^{\mathrm{d}} =\mathrm{57},\:\mathrm{find}\:\mathrm{a}+\mathrm{b}+\mathrm{c}+\mathrm{d}. \\ $$$$\mathrm{a}\neq\mathrm{b}\neq\mathrm{c}\neq\mathrm{d}\:\mathrm{and}\:\mathrm{a},\mathrm{b},\mathrm{c},\mathrm{d}\:\mathrm{are}\:\mathrm{positive} \\ $$$$\mathrm{integers}. \\ $$

Question Number 113278 Answers: 2 Comments: 0

solve ∫((√(x^2 +x+2−(√(4x^2 +4x+4))))/(x(√(x^4 +x^3 +x^2 ))))dx

$${solve} \\ $$$$\int\frac{\sqrt{{x}^{\mathrm{2}} +{x}+\mathrm{2}−\sqrt{\mathrm{4}{x}^{\mathrm{2}} +\mathrm{4}{x}+\mathrm{4}}}}{{x}\sqrt{{x}^{\mathrm{4}} +{x}^{\mathrm{3}} +{x}^{\mathrm{2}} }}{dx} \\ $$

Question Number 113275 Answers: 2 Comments: 0

∫ (dx/(3sin x+sin^3 x)) ?

$$\:\int\:\frac{\mathrm{dx}}{\mathrm{3sin}\:\mathrm{x}+\mathrm{sin}\:^{\mathrm{3}} \mathrm{x}}\:? \\ $$

Question Number 113274 Answers: 4 Comments: 2

(1) lim_(x→0) ((tan x+4tan 2x−3tan 3x)/(x^2 tan x)) (2) lim_(x→0) (((√x)−(√(sin x)))/x^(3/2) ) (3) lim_(x→0) (((√x)+(√(sin x)))/x^(5/2) )

$$\:\left(\mathrm{1}\right)\:\underset{{x}\rightarrow\mathrm{0}} {\mathrm{lim}}\:\frac{\mathrm{tan}\:\mathrm{x}+\mathrm{4tan}\:\mathrm{2x}−\mathrm{3tan}\:\mathrm{3x}}{\mathrm{x}^{\mathrm{2}} \:\mathrm{tan}\:\mathrm{x}} \\ $$$$\:\left(\mathrm{2}\right)\:\underset{{x}\rightarrow\mathrm{0}} {\mathrm{lim}}\:\frac{\sqrt{\mathrm{x}}−\sqrt{\mathrm{sin}\:\mathrm{x}}}{\mathrm{x}^{\frac{\mathrm{3}}{\mathrm{2}}} }\: \\ $$$$\:\left(\mathrm{3}\right)\:\underset{{x}\rightarrow\mathrm{0}} {\mathrm{lim}}\:\frac{\sqrt{\mathrm{x}}+\sqrt{\mathrm{sin}\:\mathrm{x}}}{\mathrm{x}^{\frac{\mathrm{5}}{\mathrm{2}}} } \\ $$

Question Number 113272 Answers: 2 Comments: 0

Solve the following equations: a)(x^2 −a)^2 −6x^2 +4x+2a=0 b)x^4 −4x^3 −10x^3 +37x−14=0,if it known that the left−hand side of the equation can be decomposed into factors with integral coefficients.

$$\mathrm{Solve}\:\mathrm{the}\:\mathrm{following}\:\mathrm{equations}: \\ $$$$\left.\mathrm{a}\right)\left(\mathrm{x}^{\mathrm{2}} −\mathrm{a}\right)^{\mathrm{2}} −\mathrm{6x}^{\mathrm{2}} +\mathrm{4x}+\mathrm{2a}=\mathrm{0} \\ $$$$\left.\mathrm{b}\right)\mathrm{x}^{\mathrm{4}} −\mathrm{4x}^{\mathrm{3}} −\mathrm{10x}^{\mathrm{3}} +\mathrm{37x}−\mathrm{14}=\mathrm{0},\mathrm{if}\:\mathrm{it} \\ $$$$\mathrm{known}\:\mathrm{that}\:\mathrm{the}\:\mathrm{left}−\mathrm{hand}\:\mathrm{side}\:\mathrm{of}\:\mathrm{the} \\ $$$$\mathrm{equation}\:\mathrm{can}\:\mathrm{be}\:\mathrm{decomposed}\:\mathrm{into} \\ $$$$\mathrm{factors}\:\mathrm{with}\:\mathrm{integral}\:\mathrm{coefficients}. \\ $$

Question Number 113271 Answers: 0 Comments: 0

solve the initial boundary value problem of wave equation ((∂^2 u(x,t))/∂t^2 )=9((∂^2 u(x,t))/∂x^2 ),0<x<2,t>0 u(0,t)=1,u(2,t)=3,t>0 u(x,0)=2,0<x<2 (∂u/∂t)(x,0)=sin2x,0<x<2

$${solve}\:{the}\:{initial}\:{boundary}\:{value} \\ $$$${problem}\:{of}\:{wave}\:{equation} \\ $$$$\frac{\partial^{\mathrm{2}} {u}\left({x},{t}\right)}{\partial{t}^{\mathrm{2}} }=\mathrm{9}\frac{\partial^{\mathrm{2}} {u}\left({x},{t}\right)}{\partial{x}^{\mathrm{2}} },\mathrm{0}<{x}<\mathrm{2},{t}>\mathrm{0} \\ $$$${u}\left(\mathrm{0},{t}\right)=\mathrm{1},{u}\left(\mathrm{2},{t}\right)=\mathrm{3},{t}>\mathrm{0} \\ $$$${u}\left({x},\mathrm{0}\right)=\mathrm{2},\mathrm{0}<{x}<\mathrm{2} \\ $$$$\frac{\partial{u}}{\partial{t}}\left({x},\mathrm{0}\right)=\mathrm{sin2}{x},\mathrm{0}<{x}<\mathrm{2} \\ $$

Question Number 113262 Answers: 2 Comments: 0

find the complex form of equation 4x^2 −2y^2 =5

$$\mathrm{find}\:\mathrm{the}\:\mathrm{complex}\:\mathrm{form}\:\mathrm{of}\: \\ $$$$\mathrm{equation}\:\mathrm{4x}^{\mathrm{2}} −\mathrm{2y}^{\mathrm{2}} =\mathrm{5} \\ $$

Question Number 113261 Answers: 1 Comments: 0

(((√((√5)+2))+(√((√5)−2)))/( (√((√5)+1))))−(√(3−2(√2)))

$$\frac{\sqrt{\sqrt{\mathrm{5}}+\mathrm{2}}+\sqrt{\sqrt{\mathrm{5}}−\mathrm{2}}}{\:\sqrt{\sqrt{\mathrm{5}}+\mathrm{1}}}−\sqrt{\mathrm{3}−\mathrm{2}\sqrt{\mathrm{2}}} \\ $$

Question Number 113246 Answers: 1 Comments: 1