Sketch a graph of the function y=cos^1x , Part I: First, sketch at least two periods of the function y = cosx
: What are the domain and range of the function y=cosx

Part III: Restrict the domain of the function

so that it may be inverted. That is, select the portion of the graph of y=cosx

that is suitable for inverting. Mark that portion on your graph from Part I.
Part IV: Now draw the reflection of this new graph of y=cosx

across the line y = x. This is a graph of the function y = cos^1x