since period for sin x is 2π so period for Y is 1.....
now put -π=2πx
so x=-1/2 here value of y=0
⇒x=-1/4 here value of y=-1
⇒x=0 here value of y=0
⇒x=1/4 here value of y=1
so x=1/2......here value of y=0
so graph draw between domain [-1/2,1/2] graph shape always same as sin function since it is depend only on total out of fn ........