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Question Number 200388 Answers: 1 Comments: 0

find all values for k such that the eq. x^3 −13x+k=0 has three integer roots.

$${find}\:{all}\:{values}\:{for}\:{k}\:{such}\:{that}\:{the}\:{eq}. \\ $$$${x}^{\mathrm{3}} −\mathrm{13}{x}+{k}=\mathrm{0}\:{has}\:{three}\:{integer}\:{roots}. \\ $$

Question Number 200403 Answers: 1 Comments: 0

∫ (((x^2 + 1)dx)/(x(x−1)(x+1))) = ??

$$ \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\int\:\:\frac{\left(\boldsymbol{{x}}^{\mathrm{2}} \:+\:\:\mathrm{1}\right)\boldsymbol{{dx}}}{\boldsymbol{{x}}\left(\boldsymbol{{x}}−\mathrm{1}\right)\left(\boldsymbol{{x}}+\mathrm{1}\right)}\:=\:?? \\ $$$$ \\ $$

Question Number 200418 Answers: 1 Comments: 0

calculus ( I ) If , I = ∫_0 ^( π) (( x )/(1 + sin^2 (x))) dx = a ζ ( 2 ) ⇒ a = ? where , ζ (s ) = Σ_(n=1) ^∞ (( 1)/n^( s) )

$$ \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\mathrm{calculus}\:\:\left(\:\:\mathrm{I}\:\:\right)\:\: \\ $$$$\:\:\mathrm{I}{f}\:,\:\:\:\mathrm{I}\:=\:\int_{\mathrm{0}} ^{\:\pi} \:\frac{\:{x}\:}{\mathrm{1}\:\:+\:\mathrm{sin}^{\mathrm{2}} \left({x}\right)}\:\mathrm{d}{x}\:=\:{a}\:\zeta\:\left(\:\mathrm{2}\:\right)\:\: \\ $$$$\:\:\:\:\:\:\:\Rightarrow\:\:\:\:{a}\:=\:?\:\:\:\:\:\:\:\:\: \\ $$$$\:\:\:\:{where}\:\:,\:\:\:\zeta\:\left({s}\:\right)\:=\:\underset{{n}=\mathrm{1}} {\overset{\infty} {\sum}}\:\frac{\:\mathrm{1}}{{n}^{\:{s}} } \\ $$$$ \\ $$

Question Number 200379 Answers: 0 Comments: 1

Question Number 200377 Answers: 1 Comments: 1

Question Number 200366 Answers: 1 Comments: 1

Question Number 200357 Answers: 0 Comments: 4

Question Number 200356 Answers: 1 Comments: 1

Question Number 200353 Answers: 3 Comments: 0

If the roots of x^3 +3px^2 +3qx+r=0 are in harmonic progression, then prove that 2q^3 =r(3pq−r)

$$\mathrm{If}\:\mathrm{the}\:\mathrm{roots}\:\mathrm{of}\:\mathrm{x}^{\mathrm{3}} +\mathrm{3px}^{\mathrm{2}} +\mathrm{3qx}+\mathrm{r}=\mathrm{0}\:\mathrm{are} \\ $$$$\mathrm{in}\:\mathrm{harmonic}\:\mathrm{progression},\:\mathrm{then}\:\mathrm{prove}\:\mathrm{that} \\ $$$$\mathrm{2q}^{\mathrm{3}} =\mathrm{r}\left(\mathrm{3pq}−\mathrm{r}\right) \\ $$

Question Number 200351 Answers: 1 Comments: 0

Solve the equation x^3 −12x^2 −6x−10=0 by cardon′s method

$$\mathrm{Solve}\:\mathrm{the}\:\mathrm{equation}\:\mathrm{x}^{\mathrm{3}} −\mathrm{12x}^{\mathrm{2}} −\mathrm{6x}−\mathrm{10}=\mathrm{0}\: \\ $$$$\mathrm{by}\:\mathrm{cardon}'\mathrm{s}\:\mathrm{method} \\ $$

Question Number 200350 Answers: 0 Comments: 1

Question Number 200336 Answers: 1 Comments: 0

Question Number 200330 Answers: 4 Comments: 0

2^x − 3^x = (√(6^x − 9^x )) find: x = ?

$$\mathrm{2}^{\boldsymbol{\mathrm{x}}} \:−\:\mathrm{3}^{\boldsymbol{\mathrm{x}}} \:=\:\sqrt{\mathrm{6}^{\boldsymbol{\mathrm{x}}} \:−\:\mathrm{9}^{\boldsymbol{\mathrm{x}}} } \\ $$$$\mathrm{find}:\:\:\:\mathrm{x}\:=\:? \\ $$

Question Number 200325 Answers: 1 Comments: 0

A point P is taken inside the rectangleC ABD. This point joins the four vertices ofh te rectangle. Knowing that PA is 15 cm. B P 24 cm and PC 20 cm find the distancef o point P from point D.

$$\mathrm{A}\:\mathrm{point}\:\mathrm{P}\:\mathrm{is}\:\mathrm{taken}\:\mathrm{inside}\:\mathrm{the}\:\mathrm{rectangleC} \\ $$$$\mathrm{ABD}.\:\mathrm{This}\:\mathrm{point}\:\mathrm{joins}\:\mathrm{the}\:\mathrm{four}\:\mathrm{vertices}\:\mathrm{ofh} \\ $$$$\mathrm{te}\:\mathrm{rectangle}.\:\:\mathrm{Knowing}\:\mathrm{that}\:\mathrm{PA}\:\mathrm{is}\:\mathrm{15}\:\mathrm{cm}.\:\mathrm{B} \\ $$$$\mathrm{P}\:\:\mathrm{24}\:\mathrm{cm}\:\mathrm{and}\:\mathrm{PC}\:\:\mathrm{20}\:\mathrm{cm}\:\mathrm{find}\:\mathrm{the}\:\mathrm{distancef} \\ $$$$\mathrm{o}\:\mathrm{point}\:\mathrm{P}\:\mathrm{from}\:\mathrm{point}\:\mathrm{D}. \\ $$

Question Number 200321 Answers: 5 Comments: 0

for x,y,z ∈N, if 38x+40y+41z=520 find x+y+z=?

$${for}\:{x},{y},{z}\:\in{N},\:{if} \\ $$$$\mathrm{38}{x}+\mathrm{40}{y}+\mathrm{41}{z}=\mathrm{520} \\ $$$${find}\:{x}+{y}+{z}=? \\ $$

Question Number 200319 Answers: 4 Comments: 0

Question Number 200318 Answers: 2 Comments: 0

Question Number 200315 Answers: 0 Comments: 3

{ (( ab ^(−) ∙ b ^(−) + ba ^(−) ∙ a ^(−) = cde ^(−) )),(( ab ^(−) ∙ b ^(−) − ba ^(−) ∙ a ^(−) = f ^(−) )) :} a,b,c,d,e,f are all different and in some order consecutive also. Determine the remaining decimal digits.

$$\:\begin{cases}{\overline {\:{ab}\:}\centerdot\overline {\:{b}\:}+\overline {\:{ba}\:}\centerdot\overline {\:{a}\:}=\overline {\:{cde}\:}}\\{\overline {\:{ab}\:}\centerdot\overline {\:{b}\:}−\overline {\:{ba}\:}\centerdot\overline {\:{a}\:}=\overline {\:{f}\:}\:}\end{cases} \\ $$$${a},{b},{c},{d},{e},{f}\:{are}\:{all}\:{different}\:{and}\:{in} \\ $$$${some}\:{order}\:{consecutive}\:{also}. \\ $$$$\: \\ $$$$\mathcal{D}{etermine}\:{the}\:{remaining}\:{decimal} \\ $$$${digits}. \\ $$

Question Number 200275 Answers: 1 Comments: 0