With the answers extra points given

Asap describe the transformations required to obtain the graph of the function f(x) from the graph of the function g(x). f(x)=-5.8sin x. g(x)=sin x. a: vertical stretch by a factor of 5.8, reflection across y-axis. b: vertical stretch by a factor of 5.8,reflection across x-axis. c: horizontal stretch by a factor of 5.8, reflection across x-axis. d: horizontal stretch by a factor of 5.8 reflection across y-axis.

Find the cosine function that is represented in the graph.

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?