Question

solve 2cos3(x-pi/4)=0

Answer 1

same as \(\cos(3(x-\frac{\pi}{4}))=0\)

Answer 2

use the "equation" option to make it luk understandable

Answer 3

for xE[-2pi,2pi]

Answer 4

\(\cos(\frac{\pi}{2})=0\) so for one solution you can solve \(3(x-\frac{\pi}{4})=\frac{\pi}{2}\) for \(x\)

Answer 5

\[2\cos3(90-(135-x) )\]

Answer 6

kk \[2\cos3(x-\frac{\pi}{4})=0 for -2\pi \le x \le 2\pi\]

Answer 7

4 cos^3 (x) - 3cos x= cos3x

Answer 8

@satellite73 um how to get rest of solutions within domain

Answer 9

im missing a few solns

Answer 10

well, you could keep solving i guess

Answer 11

probably a quicker way to do it, but you have \(\cos(\frac{3\pi}{2})=0\) so you could solve again

Answer 12

let me think if there is a snap way to find the others
probably is

Answer 13

lets do it like adults
we know that \(\cos(\frac{(2n+1)\pi}{2})=0\) so we want to solve
\[3(x-\frac{1}{4})=\frac{(2n+1)\pi}{2}\] for \(x\)

Answer 14

sorry, last line should read
\[3(x-\frac{\pi}{4})=\frac{(2n+1)\pi}{2}\]

Answer 15

is that just the general soln

Answer 16

cant you just solve this like you would any cos function ?

Answer 17

\[3x-\frac{3\pi}{4}=\frac{(2n+1)\pi}{2}\]
\[3x=\frac{(2n+1)\pi}{2}+\frac{3\pi}{4}\]
\[3x=\frac{4n\pi+2\pi+3\pi}{4}\]
\[3x=\frac{(4n+1)\pi}{4}\]
\[x=\frac{(4n+1)\pi}{12}\]

Answer 18

um so what do i do with that