Question

(1/2)^y.2^-1.(1/2)^y=(1/2)^9​

Answer 1

$\left(\dfrac12\right)^y\cdot2^{-1}\cdot\left(\dfrac12\right)^y=\left(\dfrac12\right)^9\\\\\\(2^{-1})^y\cdot2^{-1}\cdot(2^{-1})^y=(2^{-1})^9\\\\\\(2^{-y})\cdot2^{-1}\cdot(2^{-y})=-y(2^{-9})\\\\\\2^{-y+(-1)+(-y)}=2^{-9}\\\\\\2^{-2y-1}=2^{-9}\\\\\\-2y-1=-9\\\\\\-2y=-8\\\\\\y=4$