1.Describe the effects on the graphs

y = sin k0(0 is theta) and
y = cos k(0 is theta) as the value of k vaires.

normally the period of sinθ is 2pi.

When you have sin kθ, then kθ has a period of 2pi, so the sine has period 2pi/k. The effect is to contract the graph horizontally by a factor of k.

Same for cosine.