Answer
Start with $g(x)=x^{2}$,
Stretch vertically by factor 2,$\qquad 2g(x)=2x^{2}$
Lower by one unit, ,$\qquad 2g(x)-1=2x^{2}-1$
Work Step by Step
Start with $g(x)=x^{2}$,
Stretch vertically by factor 2,$\qquad 2g(x)=2x^{2}$
Lower by one unit, ,$\qquad 2g(x)-1=2x^{2}-1$