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Question Number 93170 Answers: 0 Comments: 2

x^2 +(1/x^2 )=27 (√x)+(1/(√x))=....

$${x}^{\mathrm{2}} +\frac{\mathrm{1}}{{x}^{\mathrm{2}} }=\mathrm{27} \\ $$$$\sqrt{{x}}+\frac{\mathrm{1}}{\sqrt{{x}}}=.... \\ $$

Question Number 93166 Answers: 1 Comments: 0

Question Number 93146 Answers: 0 Comments: 2

lim_(x→0) ((∫_0 ^x (a+bcos t+c cos (2t))dt)/x^5 ) = 15

$$\underset{{x}\rightarrow\mathrm{0}} {\mathrm{lim}}\:\frac{\underset{\mathrm{0}} {\overset{\mathrm{x}} {\int}}\left(\mathrm{a}+\mathrm{bcos}\:\mathrm{t}+\mathrm{c}\:\mathrm{cos}\:\left(\mathrm{2t}\right)\right)\mathrm{dt}}{\mathrm{x}^{\mathrm{5}} }\:=\:\mathrm{15} \\ $$

Question Number 93144 Answers: 1 Comments: 0

∫ ((x^3 −1)/(x^3 +6x^2 +10x)) dx

$$\int\:\frac{\mathrm{x}^{\mathrm{3}} −\mathrm{1}}{\mathrm{x}^{\mathrm{3}} +\mathrm{6x}^{\mathrm{2}} +\mathrm{10x}}\:\mathrm{dx}\: \\ $$

Question Number 93138 Answers: 2 Comments: 0

{ ((18x^2 =3y(1+9x^2 ))),((18y^2 =3z(1+9y^2 ))),((18z^2 =3x(1+9z^2 ))) :}

$$\begin{cases}{\mathrm{18x}^{\mathrm{2}} =\mathrm{3y}\left(\mathrm{1}+\mathrm{9x}^{\mathrm{2}} \right)}\\{\mathrm{18y}^{\mathrm{2}} =\mathrm{3z}\left(\mathrm{1}+\mathrm{9y}^{\mathrm{2}} \right)}\\{\mathrm{18z}^{\mathrm{2}} =\mathrm{3x}\left(\mathrm{1}+\mathrm{9z}^{\mathrm{2}} \right)}\end{cases} \\ $$

Question Number 93129 Answers: 1 Comments: 2

derive x^2 −(α+β)x+αβ

$${derive}\:{x}^{\mathrm{2}} −\left(\alpha+\beta\right){x}+\alpha\beta \\ $$

Question Number 93125 Answers: 0 Comments: 3

Question Number 93118 Answers: 1 Comments: 0

sin(x)=a −1≤a≤1

$${sin}\left({x}\right)={a} \\ $$$$−\mathrm{1}\leqslant{a}\leqslant\mathrm{1} \\ $$

Question Number 93109 Answers: 0 Comments: 2

∫_0 ^(2π) cos^(2020) (x)dx

$$\underset{\mathrm{0}} {\overset{\mathrm{2}\pi} {\int}}\:{cos}^{\mathrm{2020}} \left({x}\right){dx} \\ $$

Question Number 93098 Answers: 0 Comments: 5

find the general solution to ∫ (1/(a sin x + b cos x)) dx and ∫ (1/(a cos x − bsin x)) dx where a , b are constants.

$$\mathrm{find}\:\mathrm{the}\:\mathrm{general}\:\mathrm{solution}\:\mathrm{to} \\ $$$$\:\int\:\frac{\mathrm{1}}{{a}\:\mathrm{sin}\:{x}\:+\:{b}\:\mathrm{cos}\:{x}}\:{dx}\:\:\mathrm{and}\:\int\:\frac{\mathrm{1}}{{a}\:\mathrm{cos}\:{x}\:−\:{b}\mathrm{sin}\:{x}}\:{dx} \\ $$$$\mathrm{where}\:{a}\:,\:{b}\:\mathrm{are}\:\mathrm{constants}. \\ $$$$ \\ $$

Question Number 93091 Answers: 0 Comments: 1

Find the sum: Σ_(n=1) ^(2020) 2^2^n

$${Find}\:{the}\:{sum}: \\ $$$$\underset{{n}=\mathrm{1}} {\overset{\mathrm{2020}} {\sum}}\mathrm{2}^{\mathrm{2}^{{n}} } \\ $$

Question Number 93071 Answers: 1 Comments: 0

Question Number 95059 Answers: 0 Comments: 22

To Tinku Tara dear sir: i experienced following issues: 1. sometimes i got notification, but i didn′t see any update in the corresponding threads. what can be the reason? 2. when i activate the filter to show bookmarked posts, only some of the bookmarked posts will be displayed, others not. 3. it takes long time (some minutes, even hang up ) when the app updates after i have edited a post, added an image. (see picture below) 4. (old problem) when i leave the app just temporarily to go to an other app, the app starts again and i don′t come back to the place where i was before.

$${To}\:{Tinku}\:{Tara} \\ $$$${dear}\:{sir}:\:{i}\:{experienced}\:{following}\:{issues}: \\ $$$$\mathrm{1}.\:{sometimes}\:{i}\:{got}\:{notification},\:{but} \\ $$$${i}\:{didn}'{t}\:{see}\:{any}\:{update}\:{in}\:{the} \\ $$$${corresponding}\:{threads}.\:{what}\:{can}\:{be} \\ $$$${the}\:{reason}? \\ $$$$\mathrm{2}.\:{when}\:{i}\:{activate}\:{the}\:{filter}\:{to}\:{show} \\ $$$${bookmarked}\:{posts},\:{only}\:{some}\:{of}\:{the} \\ $$$${bookmarked}\:{posts}\:{will}\:{be}\:{displayed}, \\ $$$${others}\:{not}. \\ $$$$\mathrm{3}.\:{it}\:{takes}\:{long}\:{time}\:\left({some}\:{minutes},\right. \\ $$$$\left.{even}\:{hang}\:{up}\:\right)\:{when}\:{the}\:{app}\:{updates} \\ $$$${after}\:{i}\:{have}\:{edited}\:{a}\:{post},\:{added}\:{an} \\ $$$${image}.\:\left({see}\:{picture}\:{below}\right) \\ $$$$\mathrm{4}.\:\left({old}\:{problem}\right)\:{when}\:{i}\:{leave}\:{the}\:{app} \\ $$$${just}\:{temporarily}\:{to}\:{go}\:{to}\:{an}\:{other} \\ $$$${app},\:{the}\:{app}\:{starts}\:{again}\:{and}\:{i}\:{don}'{t} \\ $$$${come}\:{back}\:{to}\:{the}\:{place}\:{where}\:{i}\:{was} \\ $$$${before}. \\ $$

Question Number 93064 Answers: 1 Comments: 7

prove that (d/dx)x^n =nx^(n−1)

$${prove}\:{that}\: \\ $$$$\frac{{d}}{{dx}}{x}^{{n}} ={nx}^{{n}−\mathrm{1}} \\ $$

Question Number 93061 Answers: 0 Comments: 3

∫_1 ^(+∞) ((sin u)/u)du

$$\int_{\mathrm{1}} ^{+\infty} \frac{\mathrm{sin}\:\mathrm{u}}{\mathrm{u}}\mathrm{du} \\ $$

Question Number 93059 Answers: 1 Comments: 0

y^′ +2xy=cos x+2x sin x

$$\mathrm{y}^{'} +\mathrm{2xy}=\mathrm{cos}\:\mathrm{x}+\mathrm{2x}\:\mathrm{sin}\:\mathrm{x} \\ $$

Question Number 93057 Answers: 1 Comments: 1

y=b1x1+b2x2+c i need to arrange the equation for thd value of x2