2016年12月8日 · In addition, I put that the answer to this problem is x=pi/3+2(pi)n and x=5pi/3+2(Pi)n because for this problem, isolating x will give: cosx=1/2, and taking the inverse, I thought the answer would be pi/3 and 5pi/3 since their cosines are 1/2 but my textbook states that the answer is 2pi/3 instead of 5pi/3 which is really confusing because its ...

2023年11月16日 · I wanted to know why we add 2pi n (or any integer) whilst solving a trig equation and how to check if your solutions are right. For example, when doing -3/2 = -2 + sin(θ +11 π/6) (Answer is π/3 and π) you would get π/6 and 5 π/6 as solutions and then add 2p n and substituting n for either 0, 1 or 2.

2015年5月17日 · A standing wave has k=pi*n/L, because you need the displacement to be zero at each end. This means that the largest wavelength you can have is 2L. The other situation is from periodic boundary conditions, i.e. psi(x)=psi(x+L). You generally see these sorts of BCs in solid state physics, electrons in solids etc.

2022年6月18日 · If I specified a sequence as sin(2 * pi * n * 5/6) for n={0, …, N-1} and zero for other n, then I have an N-point finite length sequence that I could apply an N-point DFT. The value of N could be any natural number and can be thought of as the period for the periodic extension of the N-point signal or the N-point DFT.

2014年6月17日 · You isolate the trig function to get csc 2 = 4/3, and therefore sin 2 = 3/4, sin = +/- sqrt (3)/2, and you take the inverse sine of that. So x = pi/3, 2pi/3, -pi/3, -2pi/3. From [-pi, pi]. Normally, each of these would be +2npi, but because of the fact that pi/3 and -2pi/3 are exactly pi apart, and -pi/3 ans 2pi/3 are as well, it becomes +npi.

2016年4月21日 · If n is odd it will always be a multiple of pi/2. At pi/2, 3pi/2, 5pi/2 etc cos will always come out to 0. If n is even or 0 it will always be a multiple of pi. Cos alternates between 1 and -1 depending on the value of pi. This is why they say the answer is (-1) n/2. Ultimately for any even value of n the answer will come out to 1 or -1.

2023年6月11日 · As above, I can't make P=(2*PI*N*T)/60 work where N and T are cells. Help is appreciated, thanks :) This is the equation I need to use and I have the values in exExcelcel already for N and T. I have tried =2PI*(E2*D2)/60 and it corrects it to =PI2*(E2*D2)/60 automatically but then gives a value of 0. E2=2900 D2=0.1

2015年1月8日 · The term is: cos(pi*n/2), with n = 1,2,3,4,5,... I remember that you can convert these things into power series, because they usually alternate between 0,1, or -1. In this case this one goes 0,-1,0,1,0,...

2020年5月28日 · The usual DTFT "frequency" variable is actually a frequency-dependent angular variable:theta = omega · T = 2 pi f T, where T is the sample period.Thus, fs/2 is mapped to 2 pi fs/2 T = pi and –fs/2 is mapped to 2 pi –fs/2 T = –pi. The DFT is obtained by two modifications:

A way to visualize this would be to use the definition e = (1+1/N) N and subsequently e x = (1+x/N) N. If you start plotting this for x = 2 pi i and increasing N's you can see how the expression converges to 1.