Find the 3 smallest positive x-intercepts of the graph of
y = cos(12x) + cos(16x) + cos(20x)
and list them in increasing order.
+118609 Do you know what y=cos(x) looks like?
Graph it on desmos if you do not know..
What is its period?
Where does it first cross the x axis?
https://www.desmos.com/calculator/xbk6uv697u
Try drawing cos(12x) how does it compare?
Try drawing them, discuss it here, if you have specific questions then ask with a new post on this thread.
