What is the graph of sgn([x]) and sgn(sin x).. ?? I've tried.. But I'm not sure..

Inmathematics, thesign functionorsignum function(fromsignum,Latinfor "sign") is anoddmathematical functionthat extracts thesignof areal number. In mathematical expressions the sign function is often represented assgn.
Taht defines Signum which is easy to plot.
y=1 in the first quadrant and y=-1 in the 3^rdquadrant.

For Sgm(Sinx) apply the same defination.

Sin is positive in 1^stand 2^ndquadrant. and negative in the 3 and 4.
So divide the x axis in gradations of multiples of pi. From [0,pi] it will be a y=+1 line and for[pi, 2pi], it will be a y=-1 line. This same pattern will be periodic throughout the axis.
Mind that the negative x axis will follow the same pattern like[-pi,0] will be a negative line