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Question Number 54377 Answers: 0 Comments: 0

∫_(π/3) ^(3π/2) [ 2 cos x ] dx =

$$\underset{\pi/\mathrm{3}} {\overset{\mathrm{3}\pi/\mathrm{2}} {\int}}\:\:\left[\:\mathrm{2}\:\mathrm{cos}\:{x}\:\right]\:{dx}\:= \\ $$

Question Number 54376 Answers: 3 Comments: 3

1) calculate f(a) =∫_(−∞) ^(+∞) (dx/(x^2 +ax +1)) with ∣a∣<2 2) calculate g(a) =∫_(−∞) ^(+∞) (x/((x^2 +ax+1)^2 )) 3)find values of integrals ∫_(−∞) ^(+∞) (dx/(x^2 +(√2)x +1)) and ∫_(−∞) ^(+∞) (x/((x^2 +(√2)x +1)^2 )) 4) calculate A(θ) = ∫_(−∞) ^(+∞) (dx/(x^2 +2cosθ +1)) θ is a given real.

$$\left.\mathrm{1}\right)\:{calculate}\:\:{f}\left({a}\right)\:=\int_{−\infty} ^{+\infty} \:\:\:\frac{{dx}}{{x}^{\mathrm{2}} \:+{ax}\:\:+\mathrm{1}} \\ $$$${with}\:\:\:\mid{a}\mid<\mathrm{2} \\ $$$$\left.\mathrm{2}\right)\:{calculate}\:{g}\left({a}\right)\:=\int_{−\infty} ^{+\infty} \:\frac{{x}}{\left({x}^{\mathrm{2}} \:+{ax}+\mathrm{1}\right)^{\mathrm{2}} } \\ $$$$\left.\mathrm{3}\right){find}\:{values}\:{of}\:{integrals}\:\int_{−\infty} ^{+\infty} \:\:\frac{{dx}}{{x}^{\mathrm{2}} \:+\sqrt{\mathrm{2}}{x}\:+\mathrm{1}} \\ $$$${and}\:\int_{−\infty} ^{+\infty} \:\frac{{x}}{\left({x}^{\mathrm{2}} \:+\sqrt{\mathrm{2}}{x}\:+\mathrm{1}\right)^{\mathrm{2}} } \\ $$$$\left.\mathrm{4}\right)\:{calculate}\:{A}\left(\theta\right)\:=\:\int_{−\infty} ^{+\infty} \:\:\:\frac{{dx}}{{x}^{\mathrm{2}} \:+\mathrm{2}{cos}\theta\:+\mathrm{1}} \\ $$$$\theta\:{is}\:{a}\:{given}\:{real}. \\ $$

Question Number 54374 Answers: 0 Comments: 1

calculate h(a) =∫_(−∞) ^(+∞) ((cos(at))/(ch((t/2))))dt .

$${calculate}\:{h}\left({a}\right)\:=\int_{−\infty} ^{+\infty} \:\:\frac{{cos}\left({at}\right)}{{ch}\left(\frac{{t}}{\mathrm{2}}\right)}{dt}\:. \\ $$

Question Number 54372 Answers: 1 Comments: 3

let f(x) =∫_0 ^(2π) ((sint)/(x+sint))dt 1) calculate f(x) 2) calculate g(x) =∫_0 ^(2π) ((sint)/((x+sint)^2 )) dt 3) calculste for n∈N ∫_0 ^(2π) ((sint)/((x+sint)^n ))dt 4) calculate ∫_0 ^(2π) ((sint)/(2+sint))dt and ∫_0 ^(2π) ((sint)/((2+sint)^2 ))dt .

$${let}\:\:{f}\left({x}\right)\:=\int_{\mathrm{0}} ^{\mathrm{2}\pi} \:\:\frac{{sint}}{{x}+{sint}}{dt}\:\:\: \\ $$$$\left.\mathrm{1}\right)\:{calculate}\:\:{f}\left({x}\right) \\ $$$$\left.\mathrm{2}\right)\:{calculate}\:{g}\left({x}\right)\:=\int_{\mathrm{0}} ^{\mathrm{2}\pi} \:\:\frac{{sint}}{\left({x}+{sint}\right)^{\mathrm{2}} }\:{dt}\: \\ $$$$\left.\mathrm{3}\right)\:{calculste}\:{for}\:{n}\in{N}\:\:\:\:\int_{\mathrm{0}} ^{\mathrm{2}\pi} \:\frac{{sint}}{\left({x}+{sint}\right)^{{n}} }{dt}\: \\ $$$$\left.\mathrm{4}\right)\:{calculate}\:\int_{\mathrm{0}} ^{\mathrm{2}\pi} \:\:\:\frac{{sint}}{\mathrm{2}+{sint}}{dt}\:\:{and}\:\int_{\mathrm{0}} ^{\mathrm{2}\pi} \:\:\frac{{sint}}{\left(\mathrm{2}+{sint}\right)^{\mathrm{2}} }{dt}\:. \\ $$

Question Number 54371 Answers: 1 Comments: 1

prove that ln(z) = ∫_0 ^1 ((z−1)/(1+t(z−1)))dt .

$${prove}\:{that}\:{ln}\left({z}\right)\:=\:\int_{\mathrm{0}} ^{\mathrm{1}} \:\:\frac{{z}−\mathrm{1}}{\mathrm{1}+{t}\left({z}−\mathrm{1}\right)}{dt}\:. \\ $$

Question Number 54369 Answers: 0 Comments: 2

find lim_(x→1) (ξ(x)−(1/(x−1)))

$${find}\:{lim}_{{x}\rightarrow\mathrm{1}} \:\left(\xi\left({x}\right)−\frac{\mathrm{1}}{{x}−\mathrm{1}}\right) \\ $$

Question Number 54367 Answers: 1 Comments: 1

find ∫_1 ^(+∞) (([t])/t) t^(−p) dt interms of ξ(p) with p>0 .

$${find}\:\int_{\mathrm{1}} ^{+\infty} \:\frac{\left[{t}\right]}{{t}}\:{t}^{−{p}} {dt}\:{interms}\:{of}\:\xi\left({p}\right)\:{with}\:{p}>\mathrm{0}\:. \\ $$

Question Number 54364 Answers: 1 Comments: 0

If p is the measure of per pendicular segment from the origin on the line whose intercept are a and b.show that (1/a^2 )+(1/b^2 )=(1/p^2 )

$$\mathrm{If}\:\:\mathrm{p}\:\mathrm{is}\:\mathrm{the}\:\mathrm{measure}\:\mathrm{of}\:\mathrm{per} \\ $$$$\mathrm{pendicular}\:\mathrm{segment}\:\mathrm{from} \\ $$$$\mathrm{the}\:\mathrm{origin}\:\mathrm{on}\:\mathrm{the}\:\mathrm{line} \\ $$$$\mathrm{whose}\:\mathrm{intercept}\:\mathrm{are} \\ $$$$\mathrm{a}\:\:\mathrm{and}\:\:\:\:\mathrm{b}.\mathrm{show}\:\mathrm{that} \\ $$$$\frac{\mathrm{1}}{\mathrm{a}^{\mathrm{2}} }+\frac{\mathrm{1}}{\mathrm{b}^{\mathrm{2}} }=\frac{\mathrm{1}}{\mathrm{p}^{\mathrm{2}} } \\ $$$$ \\ $$

Question Number 54360 Answers: 2 Comments: 1

Question Number 54357 Answers: 2 Comments: 1

Question Number 54353 Answers: 0 Comments: 1

What is ∪,∩?? I want to know plz :) Have a nice day !

$${What}\:{is}\:\cup,\cap?? \\ $$$$\left.{I}\:{want}\:{to}\:{know}\:\mathrm{plz}\::\right) \\ $$$${Have}\:{a}\:{nice}\:{day}\:! \\ $$

Question Number 54341 Answers: 1 Comments: 0

Question Number 58312 Answers: 0 Comments: 4

Show that the angle θ between two unit vectors a_ ^ and b_ ^ is given by cosθ=a_ ^ •b_ ^ . Hence, given that a_ ^ =i_ cosA+j_ sinA and b_ ^ =i_ cosB−j_ sinB, prove that cos(A+B)= cosAcosB−sinAsinB.

$$\mathrm{Show}\:\mathrm{that}\:\mathrm{the}\:\mathrm{angle}\:\theta\:\mathrm{between}\:\mathrm{two}\:\mathrm{unit} \\ $$$$\mathrm{vectors}\:\underset{} {\hat {\mathrm{a}}}\:\mathrm{and}\:\underset{} {\hat {\mathrm{b}}}\:\mathrm{is}\:\mathrm{given}\:\mathrm{by}\:\mathrm{cos}\theta=\underset{} {\hat {\mathrm{a}}}\bullet\underset{} {\hat {\mathrm{b}}}. \\ $$$$\mathrm{Hence},\:\mathrm{given}\:\mathrm{that}\:\underset{} {\hat {\mathrm{a}}}=\underset{} {\mathrm{i}cosA}+\underset{} {\mathrm{j}sinA}\:\mathrm{and} \\ $$$$\underset{} {\hat {\mathrm{b}}}=\underset{} {\mathrm{i}cosB}−\underset{} {\mathrm{j}sinB},\:\mathrm{prove}\:\mathrm{that}\:\mathrm{cos}\left(\mathrm{A}+\mathrm{B}\right)= \\ $$$$\mathrm{cosAcosB}−\mathrm{sinAsinB}. \\ $$

Question Number 58313 Answers: 2 Comments: 2