What is the right way to use the option PlotLegends and "Expressions"

How do I plot the graph of x^2,x^4, in the same graph for x in [-5,5].

PlotRange->{-5,20},PlotLegends-> "Expressions"].

I thought the input would be

Plot[{Sin[x^2],Sin[x^4]},{x,-5,5},PlotRange-> {-5,20}, PlotLegends-> "Expressions"]