Question

( 1 phần 3x + 2z)²

Answer 1

\(\left(\dfrac{1}{3x}+2\text{z}\right)^2=\dfrac{1}{9x^2}+2.\dfrac{1}{3x}.2\text{z}+4\text{z}^2=\dfrac{1}{9x^2}+\dfrac{4}{3}x\text{z}+4\text{z}^2\)

Answer 2

`(1/3x+2z)^2=(1/3x)^2+2. 1/3x.2z+(2z)^2=1/9x^2+4/3xz+4z^2`