How do you find the important points to graph # f(x) = 20sin(π/6(t)) + 4#?

1 Answer
Feb 1, 2018

At x=3,9,15,21,27 (keep adding or subtracting by 6)

Explanation:

I used calculus for this: The derivative of that equation is #(20pi)/6*cos(pi/6t)# The critical points are where the derivative (or slope of the graph) equals zero, You get left with #cos(pi/6t)=0#. And using the unit circle you find that cos is 0 at #pi/2+pin# so to get #pi/6t# to #pi/2#, t=3, and then to keep adding pi you keep adding 6, so t=3,9,15,21...