Question

-(pi/4)sin(pix/4) solve for x, x >(or equal to) 0 x <(or equal to) 10 and i should end up with x= 0,4,8 how does that work?

Answer 1

is there any other info? i think it should be equal to something in order to solve for x

Answer 2

equal to 0 sorry

Answer 3

wait nevermind its -(pi/4)sin(pi*x/4) = 0
divide by -pi/4 on both sides leaving
sin(pi*x/4) = 0
now think about the graph of the sin function it is only zero at x=0,pi,2pi...

Answer 4

ohhhh but then i get where it is 0. im not gettting that once i get to sin(pi*x/4) what does the pi/4 contribute? idk if im stating that correctly

Answer 5

think of it this way
say y = pi*x/4
we know sin(y) = 0 at y=0,pi,2pi
so set up three equation
pix/4 = 0 or pi or 2pi and solve for x

Answer 6

oh ok, thats what i did wrong. i solved for 0, but i forgot that sin is 0 at pi and 2pi. and that i need to account for that too.

thank you sooo much!

Answer 7

your welcome :)