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Question Number 215625 Answers: 1 Comments: 5

x^4 +x^3 −8x^2 +2x+4=0 x=1 ∨ x=2 ∨ x=2±(√2) Is this right? I have not enough time to edit my solution

$${x}^{\mathrm{4}} +{x}^{\mathrm{3}} −\mathrm{8}{x}^{\mathrm{2}} +\mathrm{2}{x}+\mathrm{4}=\mathrm{0} \\ $$$${x}=\mathrm{1}\:\vee\:{x}=\mathrm{2}\:\vee\:{x}=\mathrm{2}\pm\sqrt{\mathrm{2}} \\ $$$$\mathrm{Is}\:\mathrm{this}\:\mathrm{right}?\:\mathrm{I}\:\mathrm{have}\:\mathrm{not}\:\mathrm{enough}\:\mathrm{time}\:\mathrm{to}\:\mathrm{edit}\:\mathrm{my}\:\mathrm{solution} \\ $$

Question Number 215608 Answers: 1 Comments: 3

Question Number 215604 Answers: 1 Comments: 0

Question Number 215598 Answers: 1 Comments: 1

Question Number 215593 Answers: 2 Comments: 2

Question Number 215589 Answers: 0 Comments: 0

jarak pada peta = skala × jarak sebenarnya

$${jarak}\:{pada}\:{peta}\:=\:{skala}\:×\:{jarak}\:{sebenarnya} \\ $$

Question Number 215588 Answers: 0 Comments: 1

jarak sebenarnya= ((jarak pada peta)/(skala))

$${jarak}\:{sebenarnya}=\:\frac{{jarak}\:{pada}\:{peta}}{{skala}} \\ $$

Question Number 215587 Answers: 0 Comments: 1

skala=((jarak di peta)/(jarak sebenarnya))

$${skala}=\frac{{jarak}\:{di}\:{peta}}{{jarak}\:{sebenarnya}} \\ $$

Question Number 215564 Answers: 2 Comments: 0

given; x(√y)+y(√x)=630 y(√y)+x(√x)=604 find x and y

$$\boldsymbol{\mathrm{given}};\:\:\boldsymbol{\mathrm{x}}\sqrt{\boldsymbol{\mathrm{y}}}+\boldsymbol{\mathrm{y}}\sqrt{\boldsymbol{\mathrm{x}}}=\mathrm{630} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\boldsymbol{\mathrm{y}}\sqrt{\boldsymbol{\mathrm{y}}}+\boldsymbol{\mathrm{x}}\sqrt{\boldsymbol{\mathrm{x}}}=\mathrm{604} \\ $$$$\boldsymbol{\mathrm{find}}\:\boldsymbol{\mathrm{x}}\:\boldsymbol{\mathrm{and}}\:\boldsymbol{\mathrm{y}} \\ $$

Question Number 215559 Answers: 2 Comments: 0

(√y) + (√x) = 5 (√x) ∙ (√y) = 8 (((√x) y − x (√y))/(y − x)) = ?

$$\sqrt{\mathrm{y}}\:+\:\sqrt{\mathrm{x}}\:=\:\mathrm{5} \\ $$$$\sqrt{\mathrm{x}}\:\centerdot\:\sqrt{\mathrm{y}}\:=\:\mathrm{8} \\ $$$$\frac{\sqrt{\mathrm{x}}\:\mathrm{y}\:−\:\mathrm{x}\:\sqrt{\mathrm{y}}}{\mathrm{y}\:−\:\mathrm{x}}\:=\:? \\ $$

Question Number 215550 Answers: 1 Comments: 0

Let u^((1)) ,u^((2)) s.t. { ((u_(tt) ^((1)) =((∂^2 /∂x_1 ^2 )+(∂^2 /∂x_i ^2 ))u^((1)) )),((u^((1)) (x_1 ,x_2 ,0)=𝛙(x_1 ,x_2 ))),((u^((1)) (x_1 ,x_2 ,0)=0)) :}, { ((u_(tt) ^((2)) =((∂^2 /∂x_1 ^2 )+(∂^2 /∂x_2 ^2 )+c^2 )u^((2)) )),((u^((2)) (x_1 x_2 ,0)=0)),((u_t ^((2)) (x_1 ,x_2 ,0)=𝛙(x_1 ,x_2 ))) :} prove:u^((2)) (x_1 ,x_2 ,t)=(1/(2𝛑))∫∫_(𝛏_1 ^2 +𝛏_2 ^2 ≤t^2 ) ((e^(𝛏_2 c) u^((1)) (x_1 ,x_2 ,𝛏_1 )d𝛏_1 d𝛏_2 )/( (√(t^2 −𝛏_1 ^2 −𝛏_2 ^2 ))))

Question Number 215540 Answers: 1 Comments: 0

∫_(Σ_(1≤i≤n) x_i ^2 ≤1) (Σ_(1≤i≤n) x_i ^2 )^m (Σ_(1≤i≤n) a_i x_i )^(2k) Π_(1≤i≤n) dx_i

$$\int_{\underset{\mathrm{1}\leq{i}\leq{n}} {\sum}{x}_{{i}} ^{\mathrm{2}} \leq\mathrm{1}} \left(\underset{\mathrm{1}\leq{i}\leq{n}} {\sum}{x}_{{i}} ^{\mathrm{2}} \right)^{{m}} \left(\underset{\mathrm{1}\leq{i}\leq{n}} {\sum}{a}_{{i}} {x}_{{i}} \right)^{\mathrm{2}{k}} \underset{\mathrm{1}\leq{i}\leq{n}} {\prod}{dx}_{{i}} \\ $$

Question Number 215535 Answers: 1 Comments: 0

∫_(Σ_(1≤i≤n) x_i ^2 ≤R^2 ) Σ_(1≤i≤n) x_i (∂f/∂x_i )Π_(1≤i≤n) dx_i =?

$$\int_{\underset{\mathrm{1}\leq{i}\leq{n}} {\sum}{x}_{{i}} ^{\mathrm{2}} \leq{R}^{\mathrm{2}} } \underset{\mathrm{1}\leq{i}\leq{n}} {\sum}{x}_{{i}} \frac{\partial{f}}{\partial{x}_{{i}} }\underset{\mathrm{1}\leq{i}\leq{n}} {\prod}{dx}_{{i}} =? \\ $$

Question Number 215525 Answers: 1 Comments: 0

Φ :R^2 →R^2 (x.;y)∣→(2x+3y:3y) find Φ∈L(R^2 ) find ker(Φ) and the im(Φ) f o f =?

$$\Phi\::\mathbb{R}^{\mathrm{2}} \rightarrow\mathbb{R}^{\mathrm{2}} \: \\ $$$$\:\:\:\left({x}.;{y}\right)\mid\rightarrow\left(\mathrm{2}{x}+\mathrm{3}{y}:\mathrm{3}{y}\right) \\ $$$${find} \\ $$$$ \\ $$$$ \\ $$$$ \\ $$$$\Phi\in\mathscr{L}\left(\mathbb{R}^{\mathrm{2}} \right) \\ $$$${find}\:{ker}\left(\Phi\right)\:{and}\:{the}\:{im}\left(\Phi\right) \\ $$$${f}\:{o}\:{f}\:=? \\ $$$$ \\ $$

Question Number 215523 Answers: 2 Comments: 2

Two friends set off by train at dawn to visit each other. The two friends caught sight of each other through the window as the trains passed in opposite direction on adjacent tracks− it was 12^(oo) hours. The friends helplessly reached their destinations. If the first of them reached their destination at 16^(oo) and the second at 21^(oo) , what time did dawn break on that day ? Help me, please

$$ \\ $$$$\:\:\:\mathcal{T}{wo}\:{friends}\:{set}\:{off}\:\:{by}\:{train}\:{at}\:{dawn}\:{to}\:{visit} \\ $$$$\:\:\:{each}\:{other}.\:{The}\:{two}\:{friends}\:{caught}\:{sight}\:{of} \\ $$$$\:\:\:{each}\:{other}\:{through}\:{the}\:{window}\:{as}\:{the}\:{trains}\: \\ $$$$\:\:\:{passed}\:{in}\:{opposite}\:{direction}\:{on}\:{adjacent}\:{tracks}− \\ $$$$\:\:\:{it}\:{was}\:\mathrm{12}^{{oo}} \:{hours}.\:{The}\:{friends}\:{helplessly}\:{reached}\: \\ $$$$\:\:\:{their}\:{destinations}.\:{If}\:{the}\:{first}\:{of}\:{them}\:{reached}\: \\ $$$$\:\:\:{their}\:{destination}\:{at}\:\mathrm{16}^{{oo}} \:{and}\:{the}\:{second}\:{at}\:\mathrm{21}^{{oo}} , \\ $$$$\:\:\:{what}\:{time}\:{did}\:{dawn}\:{break}\:{on}\:{that}\:{day}\:? \\ $$$$\:\:\:{Help}\:{me},\:{please} \\ $$

Question Number 215520 Answers: 2 Comments: 0

Prove that { ((x = ((7 cos t − 2)/(2 − cos t)))),((y = ((4(√3) sin t)/(2 − cos t)))) :} is a circle.

$$\mathrm{Prove}\:\mathrm{that}\:\begin{cases}{{x}\:=\:\frac{\mathrm{7}\:\mathrm{cos}\:{t}\:−\:\mathrm{2}}{\mathrm{2}\:−\:\mathrm{cos}\:{t}}}\\{{y}\:=\:\frac{\mathrm{4}\sqrt{\mathrm{3}}\:\mathrm{sin}\:{t}}{\mathrm{2}\:−\:\mathrm{cos}\:{t}}}\end{cases}\:\mathrm{is}\:\mathrm{a}\:\mathrm{circle}. \\ $$

Question Number 215519 Answers: 1 Comments: 0

Find ((y/x))^(log_(x/y) (y/x) ) below: 2x^2 + xy − 3y^2 = 0

$$ \\ $$$$\:\:\:\:\:\:\:\boldsymbol{\mathrm{Find}}\:\left(\frac{\boldsymbol{\mathrm{y}}}{\boldsymbol{\mathrm{x}}}\right)^{\boldsymbol{\mathrm{log}}_{\frac{\boldsymbol{\mathrm{x}}}{\boldsymbol{\mathrm{y}}}} \frac{\boldsymbol{\mathrm{y}}}{\boldsymbol{\mathrm{x}}}\:} \boldsymbol{\mathrm{below}}: \\ $$$$ \\ $$$$ \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\mathrm{2}\boldsymbol{\mathrm{x}}^{\mathrm{2}} \:+\:\boldsymbol{\mathrm{xy}}\:−\:\mathrm{3}\boldsymbol{\mathrm{y}}^{\mathrm{2}} \:=\:\mathrm{0} \\ $$$$ \\ $$

Question Number 215504 Answers: 1 Comments: 0

simplify a−{b^(c−b) +⟨(b^(c−b) )^2 +((a/2))^2 ⟩+(a/2)}+c^(ab−c) −c^(a−c)

$$\mathrm{simplify}\:{a}−\left\{{b}^{{c}−{b}} +\langle\left({b}^{{c}−{b}} \right)^{\mathrm{2}} +\left(\frac{{a}}{\mathrm{2}}\right)^{\mathrm{2}} \rangle+\frac{{a}}{\mathrm{2}}\right\}+{c}^{{ab}−{c}} −{c}^{{a}−{c}} \\ $$

Question Number 215527 Answers: 1 Comments: 0

t_(33) ′ab+t_(00) ′ab=? Clearing up defintions: t_(33) ′a=(a−(√(36)))×3 t_(00) ′a=(a−(√(36)))×0 t′a=a−(√(36)) t′a= “transformation” of a