Question

Can this be solved w/o graphing?
sin 3x = cos x

Answer 1

I think you will need to use triple angle identities

Answer 2

you use the double angle formula or half angle formula

Answer 3

i dont know if it possible to find exact solutions

Answer 4

it is because because you haave to play around with it to find the correct answer it sums up to equal the other side

Answer 5

oh i got it

Answer 6

we have sin3x=sin(pi/2-x)
3x=pi/2-x
4x=pi/2
x=pi/8

Answer 7

just keep trying

Answer 8

i dont have to i got it lol

Answer 9

well congratz

Answer 10

we call also make a answer general by saying x=pi/8+2npi for n=..-2,-1,0,1,2,...

Answer 11

yu can say that but stil make sure that is definately the right answer its alwayz good to double check

Answer 12

and
we also have x=5pi/8+2npi for n=..-2,-1,0,1,2,..

Answer 13

\[x=\frac{\pi}{4}+\pi k\quad\vee\quad x=\frac{\pi}{8}+\frac{\pi}{2}k\quad,\quad k\in\mathbb{Z}\]