Question and Answers Forum

AllQuestion and Answers: Page 741

Question Number 144291 Answers: 1 Comments: 0

Question Number 144282 Answers: 1 Comments: 0

I=∫_(π/6) ^(π/3) ((sin^(2021) x)/(sin^(2021) x+cos^(2021) x))dx=?

$$\mathrm{I}=\int_{\frac{\pi}{\mathrm{6}}} ^{\frac{\pi}{\mathrm{3}}} \frac{\mathrm{sin}^{\mathrm{2021}} \mathrm{x}}{\mathrm{sin}^{\mathrm{2021}} \mathrm{x}+\mathrm{cos}^{\mathrm{2021}} \mathrm{x}}\mathrm{dx}=? \\ $$

Question Number 144273 Answers: 1 Comments: 0

Question Number 144272 Answers: 1 Comments: 0

S_n =Σ_(n=1) ^n (1/2^k )tanh((1/2^k ))=?

$$\mathrm{S}_{\mathrm{n}} =\underset{\mathrm{n}=\mathrm{1}} {\overset{\mathrm{n}} {\sum}}\frac{\mathrm{1}}{\mathrm{2}^{\mathrm{k}} }\mathrm{tanh}\left(\frac{\mathrm{1}}{\mathrm{2}^{\mathrm{k}} }\right)=? \\ $$

Question Number 144271 Answers: 3 Comments: 1

a,b,c are in G.P. If a^x =b^y =c^z prove that (1/x),(1/z) are in A.P.

$${a},{b},{c}\:{are}\:{in}\:{G}.{P}.\:{If}\:{a}^{{x}} ={b}^{{y}} ={c}^{{z}} \\ $$$${prove}\:{that}\:\frac{\mathrm{1}}{{x}},\frac{\mathrm{1}}{{z}}\:{are}\:{in}\:{A}.{P}. \\ $$

Question Number 144270 Answers: 1 Comments: 0

Question Number 144269 Answers: 1 Comments: 0

∫_0 ^( ∞) ⌊(y^3 /(e^y −1))⌋dy

$$\int_{\mathrm{0}} ^{\:\infty} \lfloor\frac{{y}^{\mathrm{3}} }{{e}^{{y}} −\mathrm{1}}\rfloor{dy} \\ $$

Question Number 144268 Answers: 2 Comments: 0

Question Number 144264 Answers: 0 Comments: 0

Let a,b > 0 and 2a+b = 3. Prove the followings: (1) (2/n)a(b+4)+3b^(1/n) ≤ ((10+3n)/n), ∀n∈N^+ ≥1. (2) 2na(b+4)+3b^n ≥ 10n+3, ∀n∈N^+ ≥2.

$$\mathrm{Let}\:{a},{b}\:>\:\mathrm{0}\:\mathrm{and}\:\mathrm{2}{a}+{b}\:=\:\mathrm{3}.\:\mathrm{Prove}\:\mathrm{the}\:\mathrm{followings}:\:\:\:\:\:\:\:\:\:\: \\ $$$$\left(\mathrm{1}\right)\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\frac{\mathrm{2}}{{n}}{a}\left({b}+\mathrm{4}\right)+\mathrm{3}{b}^{\frac{\mathrm{1}}{{n}}} \:\leqslant\:\frac{\mathrm{10}+\mathrm{3}{n}}{{n}},\:\forall{n}\in\mathbb{N}^{+} \geqslant\mathrm{1}. \\ $$$$\left(\mathrm{2}\right)\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\mathrm{2}{na}\left({b}+\mathrm{4}\right)+\mathrm{3}{b}^{{n}} \:\geqslant\:\mathrm{10}{n}+\mathrm{3},\:\forall{n}\in\mathbb{N}^{+} \geqslant\mathrm{2}. \\ $$$$ \\ $$

Question Number 144261 Answers: 1 Comments: 1

Find the value of lim_(n→∞) Σ_(k=n) ^(2n) (((−1)^k )/k).

$$\mathrm{Find}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\:\underset{{n}\rightarrow\infty} {\mathrm{lim}}\:\underset{{k}={n}} {\overset{\mathrm{2}{n}} {\sum}}\:\frac{\left(−\mathrm{1}\right)^{{k}} }{{k}}. \\ $$

Question Number 144260 Answers: 2 Comments: 0

Find the sum of all the real number x that satisfy (2x^2 +5x+1)^(2x−3) =1

$$\mathrm{Find}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{all}\:\mathrm{the}\:\mathrm{real}\:\mathrm{number} \\ $$$${x}\:\mathrm{that}\:\mathrm{satisfy}\:\left(\mathrm{2}{x}^{\mathrm{2}} +\mathrm{5}{x}+\mathrm{1}\right)^{\mathrm{2}{x}−\mathrm{3}} =\mathrm{1} \\ $$

Question Number 144249 Answers: 2 Comments: 0

((√(5 + 2(√6))))^z + ((√(5 - 2(√6))))^z = 10 Find: z=?

$$\left(\sqrt{\mathrm{5}\:+\:\mathrm{2}\sqrt{\mathrm{6}}}\right)^{\boldsymbol{{z}}} \:+\:\left(\sqrt{\mathrm{5}\:-\:\mathrm{2}\sqrt{\mathrm{6}}}\right)^{\boldsymbol{{z}}} \:=\:\mathrm{10} \\ $$$${Find}:\:\boldsymbol{{z}}=? \\ $$

Question Number 144248 Answers: 1 Comments: 0

Question Number 144246 Answers: 1 Comments: 0

A=lim_(n→+∝) [(1/(1^2 +3(1)+2)) + (1/(2^2 +3(2)+2)) +..+ (1/(n^2 +3n+2))]

$$\mathrm{A}=\underset{\mathrm{n}\rightarrow+\propto} {\mathrm{lim}}\left[\frac{\mathrm{1}}{\mathrm{1}^{\mathrm{2}} +\mathrm{3}\left(\mathrm{1}\right)+\mathrm{2}}\:+\:\frac{\mathrm{1}}{\mathrm{2}^{\mathrm{2}} +\mathrm{3}\left(\mathrm{2}\right)+\mathrm{2}}\:+..+\:\frac{\mathrm{1}}{\mathrm{n}^{\mathrm{2}} +\mathrm{3n}+\mathrm{2}}\right] \\ $$

Question Number 144245 Answers: 2 Comments: 0

∫_0 ^1 (x^(2n) /((x−1)^n ))dx

$$\int_{\mathrm{0}} ^{\mathrm{1}} \frac{{x}^{\mathrm{2}{n}} }{\left({x}−\mathrm{1}\right)^{{n}} }{dx} \\ $$

Question Number 144244 Answers: 1 Comments: 0

I=∫_0 ^(π/2) ((5tan^4 x+3cot^4 x)/(tan^4 x+cot^4 x))dx=?

$$\mathrm{I}=\int_{\mathrm{0}} ^{\frac{\pi}{\mathrm{2}}} \frac{\mathrm{5tan}^{\mathrm{4}} \mathrm{x}+\mathrm{3cot}^{\mathrm{4}} \mathrm{x}}{\mathrm{tan}^{\mathrm{4}} \mathrm{x}+\mathrm{cot}^{\mathrm{4}} \mathrm{x}}\mathrm{dx}=? \\ $$

Question Number 144241 Answers: 2 Comments: 0

calculate ∫_0 ^(4π) (dx/((2+cosx)^2 ))

$$\mathrm{calculate}\:\int_{\mathrm{0}} ^{\mathrm{4}\pi} \:\frac{\mathrm{dx}}{\left(\mathrm{2}+\mathrm{cosx}\right)^{\mathrm{2}} } \\ $$

Question Number 144237 Answers: 2 Comments: 0

Question Number 144234 Answers: 1 Comments: 0

∫ ((√(x^2 - x))/x^3 ) dx = ?

$$\int\:\frac{\sqrt{{x}^{\mathrm{2}} \:-\:{x}}}{{x}^{\mathrm{3}} }\:{dx}\:=\:? \\ $$

Question Number 144231 Answers: 1 Comments: 0

.....Nice ...Calculus if :: ϕ ( n ) := ∫_0 ^( 1) (x^( n) /(1 + x)) dx then :: Σ_(n=1) ^( ∞) (((−1)^(n−1) ϕ (n ))/n) =? ........

$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:.....{Nice}\:...{Calculus} \\ $$$$\:\:\:\:\:\:{if}\:\:::\:\: \\ $$$$\:\:\:\:\:\:\:\varphi\:\left(\:{n}\:\right)\::=\:\int_{\mathrm{0}} ^{\:\mathrm{1}} \frac{{x}^{\:{n}} }{\mathrm{1}\:+\:{x}}\:{dx} \\ $$$$\:\:\:\:\:{then}\:\:::\:\:\:\underset{{n}=\mathrm{1}} {\overset{\:\infty} {\sum}}\frac{\left(−\mathrm{1}\right)^{{n}−\mathrm{1}} \:\varphi\:\left({n}\:\right)}{{n}}\:=? \\ $$$$\:\:\:\:\:\:\:........ \\ $$

Question Number 144226 Answers: 1 Comments: 1

Question Number 144222 Answers: 0 Comments: 0

find ∫_0 ^∞ ((log^2 x)/((x^2 −x+1)^2 ))dx

$${find}\:\int_{\mathrm{0}} ^{\infty} \:\frac{{log}^{\mathrm{2}} {x}}{\left({x}^{\mathrm{2}} −{x}+\mathrm{1}\right)^{\mathrm{2}} }{dx} \\ $$

Question Number 144221 Answers: 0 Comments: 0

find ∫_0 ^∞ e^(−3x) log^2 (1+e^(2x) )dx

$${find}\:\int_{\mathrm{0}} ^{\infty} {e}^{−\mathrm{3}{x}} {log}^{\mathrm{2}} \left(\mathrm{1}+{e}^{\mathrm{2}{x}} \right){dx} \\ $$

Question Number 144220 Answers: 1 Comments: 0

find A_n =∫_0 ^1 arctan(x^n )dx n ∈N

$${find}\:{A}_{{n}} =\int_{\mathrm{0}} ^{\mathrm{1}} \:{arctan}\left({x}^{{n}} \right){dx} \\ $$$${n}\:\in{N} \\ $$

Question Number 144219 Answers: 1 Comments: 0

let f(x)=(1/((2+cosx)^2 )) developp f at fourier serie

$${let}\:{f}\left({x}\right)=\frac{\mathrm{1}}{\left(\mathrm{2}+{cosx}\right)^{\mathrm{2}} } \\ $$$${developp}\:{f}\:{at}\:{fourier}\:{serie} \\ $$

Question Number 144218 Answers: 1 Comments: 0

U_n =Σ_(k=0) ^n (1/( (√(2k+1)))) find a eqivalent of U_n (n→∞)

$${U}_{{n}} =\sum_{{k}=\mathrm{0}} ^{{n}} \frac{\mathrm{1}}{\:\sqrt{\mathrm{2}{k}+\mathrm{1}}} \\ $$$${find}\:{a}\:{eqivalent}\:{of}\:{U}_{{n}} \left({n}\rightarrow\infty\right) \\ $$

Pg 736 Pg 737 Pg 738 Pg 739 Pg 740 Pg 741 Pg 742 Pg 743 Pg 744 Pg 745

Contact: info@tinkutara.com