b) ( 2x+3)^2 - (2x+1)(2x-1) =22
=> 4x2+12x+9-4x2+1=22
=> 12x=12
=>x=1
c) (4x+3)(4x-3) -(4x-5)^2 =16
=>16x2-9-16x2+40x-25=16
=>40x=50
=>x=4/5
a)\(\left(x-13\right)^2-4=0\\\left(x-13\right)^2=4\\ \left(x-13\right)^2=2^2\\ \Rightarrow\left\{{}\begin{matrix}x-13=2\\x-13=-2\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}15\\-11\end{matrix}\right.\)
vậy...
d) x^3 -9x^2 +27x-27 =-8
=>(x-3)3=-8
=>x-3=-2
=>x=1
e) (x+1)^3 - x^2(x+3) =2
=>x3+3x2+3x+1-x3-3x2=2
=>3x=1
=>x=1/3