\( x^{3} \cdot x^{\stackrel{2}{?}}=\frac{1}{x^{12}} \)
\( y=-15 \)
Step 1 :\( x^3 \cdot x^y = x^{3+y} \)
Step 2 :\( x^{3+y} = \frac{1}{x^{12}} \)
Step 3 :\( 3+y=-12 \)
Step 4 :\( y=-15 \)