Sin Definition and 452 Threads

Homework Statement Hey guys. I need to find the Fourier transform of sin, is this right? http://img156.imageshack.us/img156/5531/scan0004r.jpg I searched the internet but all I could find is the answer with the dirac delta and I don't need that. Thanks. Homework Equations...

Determine whether this converges. If so, what number? http://texify.com/img/\LARGE\!\Sigma[/URL] _{0}^{ \infty } \sin^n (\frac{ \pi }{4} %2B n \pi).gif[/PLAIN] When I start plugging in values, I get : n= 0 f(n)=1 n=1 f(n)= -\sqrt{2}/2 n=2 f(n)= \sqrt{2}/2 Using the...

Homework Statement I was given the series sin 1 + sin 2 + sin 3 + sin 4 + ... and I must show that it diverges. Can anyone point me in the right direction as to how to go about doing this? Homework Equations The Attempt at a Solution

Homework Statement This isn't really a problem, just a question... If you had sin(x) / sin^2(x), you are left with 1/sin(x), right? So how come when you have sin(x)*arcsin(x) you aren't left with 1? Isn't arcsin(x) the same as writing sin^-1 (x)? Therefore writing sin(x)arcsin(x)...

Homework Statement I am supposed to show that this statement holds true (csc x + cot x) / (tan x + sin x) = cot x * csc x using sohcahtoa Homework Equations The Attempt at a Solution I have tried this (( h/o ) + (a/o ) / ( o/a + o/h)) 1st (( ah / o sqrd )) + ((ah / o...

Homework Statement Homework Equations The Attempt at a Solution

Hi I was wondering if there is a non-numericla way to solve the following equation: 144 - 90sin x - 155.8cos x = 0 Thanks

For two arbitrary vectors in 3D space, subtending an angle, \gamma , I know the cos relationship, but what's the sin relationship ? I ask because there is an ambiguity by only knowing the cosine form, since vector A can be either above or below vector B. cos\gamma = cos\theta_1...

For two arbitrary vectors, subtending an angle, \gamma , I know the cos relationship, but what's the sin relationship ? I ask because there is an ambiguity by only knowing the cosine form, since vector A can be either above or below vector B. cos\gamma = cos\theta_1 cos\theta_2 + sin\theta_1...

Homework Statement Integrate (sin5x)(cos4x)dx Homework Equations The Attempt at a Solution I tried substituting u as (sin5x), but wound up with something way more complicated than what I started with. Same thing happens if I substitute cos^4 for u. I have no idea what to try...

Homework Statement Compute \int^{\pi/2}_{0} \frac{sin^{2009}x}{sin^{2009}x + cos^{2009}x} I used the identity cos^{2}= 1 - sin^{2}, but instead I set the exponent as 2009. And so I ended up with the answer being -1. I'm just wondering whether this is a legal solution or am I not allowed to...

Homework Statement Ok so we started Fourier Analysis in circuits. How can i tell the Period of a function that's let's say sin(2t)+3cos(5t) something like that . Any help or url's that have information on this

Homework Statement The two sides of a stepladder are of length 2m and 1.85m. When fully opened, the longer side is inclined at 65° to the horizontal. Find the distance apart of the feet of the step ladder. Homework Equations Sin Rule & Pythagoras? The Attempt at a Solution I had a go but I...

Hi, I get really confused when to use the cos function or the sin function. for example, I was looking at this yesterday and thought the other way around of the correct answer. Why did it chose sin function for tension and cos function for the normal force? This problem doesn't explain why it...

First of all, hi I'm new here my name is crisanna. I stumbled upon this site across the web and realized this 's a great site! Anyway , here 's my question. Does anyone know how to integrate sin (1 +cos ^2 x) ? I tried the method integrate by parts but I got stucked. Below is my attempt : u=...

The question asks me to integrate x^2 sin x dx and then use it to find the exact value of the integration of abs ( x^2 sin x dx) with upper limit of pi/2 and lower limit of -pi/2. I have found the integration of x^2 sin x dx which is -x^2 cosx + 2xsinX + 2 cosx + C but after putting in the...

Homework Statement Im wondering if this question could be solved. Given that sin theta =a+b and cos theta =a-b Find tan theta when a/b=3 Solved alr.. the ans is 2. Homework Equations The Attempt at a Solution

Homework Statement y = sin \pix Using arc length and surface revoultion on x-axis 0 <= x <= 1 The Attempt at a Solution d/dx sin \pix = \pi cos \pix (\pi cos\pix)^2 = \pi^2 cos^2\pix \int sin pi * x * 2 * pi * \sqrt{1 + pi^2 * cos^2 (pi*x)} u = pi cos (pi * x) du = -pi^2 * sin...

Ok so i have a function cos4/3x between 0<= X <= 2π the amp is 1, max is 1 and min is -1. the period is 3π/2. normally in a cos graph, π/2=0, π=-1, 3π/2=0 and 2π=1. but since the period is 3π/2, i know the 1 is now at 3π/2. But I am getting confused as to where the 0s and the negative -1...

Sin [Pi. (x-1)] / x-1; for x =1,2,3,...N Sin [ Pi. (x-1) ] / (x-1) = ? for x=1,2,3,4,...N I think for Sin (x) / x =1 but, what about that.

For different values of x in positive increasing order,sin wave would be either Max or Min, so I plotted all points.how to find out whether wave is max or min at a given particular point from X. Thanks.

hi there. I have an expression Sqrt of 0.6 / 0.2 x sin ^2 however it is giving an error on the calculator. the equation am trying to work out is : x = 25 x 10 ^ - 9 x sin ^ - 1 (Square Root of 0.6 / 0.2 x sin ^ 2) (4 x 25)) / ∏ x 4 x 10 ^ - 6 how can I work out x when am getting...

Homework Statement sin²(1°)+sin²(3°)+sin²(5°)+...sin²(359°)= ? And : 1!+2!+3!+4!+...+2006!, asked are he last two numbers of this sum. Homework Equations I don't know anyThe Attempt at a Solution I don't know how to calculate Sin with your head, and 2006! is way to hard to calculate. Is...

i understand that non monotonic is neither decreasing nor increasing does it mean sin n is also non monotonic ?

Homework Statement I have been given these two equations: x=2acos^2(x) , y = 2a(cos(x))(sin(x)) where a ranges from 0 to 5 and -2π < x < 2π I need to prove that these equations (when you plug in values for x) create points that when plotted, give you a circle with center (x-a) and radius a...

How do I solve: [sin (pi/3)] + [cos (pi/6)]? <--- "pi" is 3.14... I think that [sin (pi/3)]= (square root 3) divided by 2 AND that [cos (pi/6)]= (square root 3) divided by 2. Now I can't remember how to add fractions containing square roots. My textbook...

f(x)=x4 cos(2/x6) g(x) <= f(x) <= h(x) how to get g(x) and h(x) by using the squeeze theorem?? I know is something like this -1 <= x <= 1 But how do i implement it here, and especially to the cos, sin, and tan??

f(x) = 9 sin 7 x, and g(x) = 18 sin(7 x + 5) so, i assume by looking just like this g(x) is twice much more than f(x) and 5 units more, correct??

Hi. I believe this may have been addressed previously but I wanted to make sure since I don't think it was completed. Hi I know that differentiating sin = cos , and differentiating cos = -sin. Time to prove it. Q3: Prove that: \frac{d}{{dz}}\sin z = \cos z We know the McLaurin form...

Homework Statement Just a general questions I don't understand. Why is it sin A in a cross product and not cos A? I don't understand it in the equation F=qvBsinA Homework Equations no The Attempt at a Solution ...

I'm working through Kline's Calculus book, and am at the chapter on Integration on Differentiation of Trig Functions. A question asks to find the derivative of: (I've labeled all equations for easy reference) (1) y = sin x * cos x unlike the solution guide which advocates using the product...

soine cosine rule I have a question for you, I came across this question while revising for my exam on monday if anyone can answer this I'll be very impressed. Two different trangles ABC have AB=5cm, AC=3.2cm and angle ABC=35degrees calculate the difference between their areas.

Homework Statement Integrate \int\sin 6x + 3\cos 5x dx Homework EquationsThe Attempt at a Solution The way I was taught was the 'u' substitution method. I know that \int\sin u du = -\cos u + C and I know that \int\cos u du = \sin u + C Here's what I've done so far \int\sin 6x + 3\cos 5x...

[SOLVED] sin function Homework Statement My complex analysis book says, "from calculus, \sin \theta \leq \theta for 0 \leq \theta \leq \pi/2 ." Could someone please give me a better reason why that is true?Homework Equations The Attempt at a Solution

TRIG~ Law of Sin - Law of Cos HELP PLZ! hey i need some help... so umm please help me

Homework Statement Derive... x(t)=(exp^(-\zeta\omegat))*(a1(exp^(i\omegasqrt(1-\zeta^2)*t)))+a2(exp^(-i\omegasqrt(1-\zeta^2)*t)))) into x(t)=(exp^(-\zeta\omegat))*(A sin (\omega*t + \varphi)) Homework Equations n/a The Attempt at a Solution I've managed to get x(t) =...

Homework Statement 4sec180° - 2sin2270° The Attempt at a Solution sec(180 is -1. So we have 4(-1) which is -4 sin2(270 is -1 So we have 2(-1) This now reads -4 - -2 Answer = -2 Is this correct or do I suck at this? =(

Greetings, I've solved (almost) a problem - with the answer involving sin(). My first solution involves values for which sin() is equal to 0.5 - i.e.30 degrees or 0.5235. The internal of the sin function is sin(10t -0.927) t = 0.1451 To complete this solution I need to show the...

Homework Statement does (\sin{z})^* = \sin{z^*}? (where z is a complex number) Homework Equations \sin{z} = \frac{1}{2} (e^{iz} - e^{-iz}) The Attempt at a Solution (\sin{z})^* = \frac{1}{2} (e^{iz} - e^{-iz})^* = \frac{1}{2} (e^{-iz^*} - e^{iz^*}) = -\frac{1}{2} (e^{iz^*} - e^{-iz^*}) =...

urgent: sines if you are given a point on the terminal side of an angle 0 , explain how to find sin 0 Please i really need help with this one

Hi. Could someone please help me with the following C3 question? I would really appreciate any help as I am completely stuck at the moment. Find, in terms of pi, the solutions of the equation sin5x + sin x = 0 for x in the interval 0 >= x > pi. I wrote down that sin(3x + 2x) + sin x = 0...

Im having an issue of when to use Cos and Sin. When calculating Force (Normal and Frictional) with multiple demension problems you are typically given the angle of the incline. When trying to calculate for Fgx (or basically x) I would think to use cos(theta) and when dealing with Fgy (or...

Sin x = 2/pi How do you solve for x?? I am drawing a blank! I did sin-1 ( 2/pi) = 0.69 but I need another value cause I am also supposed to get 2.451?

Homework Statement the question is Find the measure of the indicated angle, to the nearest tenth of a degree. Heres a picture of the question. (sorry for the bad quality) http://img107.imageshack.us/img107/7002/mathproblem2bb2.jpg ok for c) and d) I've applied what I've learned during the...

Prove that \sin (n^2) + \sin (n^3) is not a convergent sequence.

Okay so I am suposed to evaluate 2 of these: 1.) \int\sin^3(a\theta)d\theta the solution manual looks like it used a trig ID to do this. Why?? Doesn't \int\sin^3u du=\frac{1}{3}\cos^3u-(\cos u)+C ? So just use the u-sub u=a\theta \Rightarrow du/a=d\theta So it should just be...

Should I make acceleration the y-axis and sin of theta the x-axis or the other way around? If this adds to anything, as the sin of theta decreases, the acceleration is also decreasing...

Can someone tell me where I can find a complete proof of the infinite series used to find the arcsin? thanks in advance.

Homework Statement what is the frequecy F for the alterating current U(T)=15cos(314t) A Homework Equations Am really new at this kind of problem but i think 314 is how many times the current rotates or fluxuates in 1 period so the F has to be the distance between waves? The...

My teacher told me that C sin(k x) + D cos(k x) = F sin(k x+gamma) if neither C nor D is 0 (gamma is a phase angle). How do you derive the expression on the right of the equal sign from that on the left?