a)
Se $\,x^{\large 2}\,=\,4\,$ então $\,x^{\large 6}\,=\,64\,$
b)
Se $\,x^{\large 6}\,=\,64\,$ então $\,x\,=\,2\,$
c)
$\,\left(2^{\large 2}\right)^{\large 3}\,< \,2^{\large 2^3}\,$
d)
Se $\,10^{\large x}\,=\,0,2\,$ então $\,10^{\large 2x}\,=\,0,4\,$
e)
$\,2^{\large n+2}\,+\,2^{\large n}\,= \,5\centerdot\,2^{\large n}\,$
