Giải thích các bước giải:

a.$2^3x=2^8$

$\to x=2^5$

b.$x:(\dfrac15)^3=(\dfrac15)^6$

$\to x=(\dfrac15)^9$

c.$\dfrac13+(\dfrac23)^2x=\dfrac{51}{81}$ 

$\to (\dfrac23)^2x=\dfrac{8}{27}$

$\to \dfrac49x=\dfrac8{27}$

$\to x=\dfrac23$

d.$4x=16^2$

$\to 4x=256$

$\to x=64$

e.$(\dfrac56)^{13}:x=\dfrac{25}{36}$

$\to (\dfrac56)^{13}:x=(\dfrac56)^2$

$\to x=(\dfrac56)^{13}:(\dfrac56)^2$

$\to x=(\dfrac56)^{11}$

f.$(x+1)^3=27$

$\to (x+1)^3=3^3$

$\to x+1=3$

$\to x=2$