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Đáp án:

`1)`

`(5x+3yz)^2`

`=(5x)^2+2.5x.3yz+(3yz)^2`

`=25x^2+30xyz+9y^z^2`

`2)`

`(y^2x-3ab)^2`

`=(y^2x)^2-2.y^2x.3ab+(3ab)^2`

`=y^4x^2-6xy^2ab+9a^2b^2`

`=y^4x^2+(-6xy^2ab)+9a^2b^2`

`3)`

`(x^2-6z)(x^2+6z)`

`=(x^2)^2-(6z)^2`

`=x^4-36z^2`

`=x^4+(-36z^2)`

`4)`

`(5x+2y)^2`

`=(5x)^2+2.5x.2y+(2y)^2`

`=25x^2+20xy+4y^2`

`5)`

`(-3x+2)^2`

`=(-3x)^2+2.(-3x).2+2^2`

`=9x^2-12x+4`

`=9x^2+(-12x)+4`

`6)`

`(2/3x+1/3y)^2`

`=(2/3x)^2+2. 2/3x . 1/3y+(1/3y)^2`

`=4/9x^2+4/9xy+1/9y^2`

`7)`

`(2x-5/2y)^2`

`=(2x)^2-2.2x. 5/2y+(5/2y)^2`

`=4x^2-10xy+25/4y^2`

`=4x^2+(-10xy)+25/4y^2`

`8)`

`(x+4/3y^2)^2`

`=x^2+2.x. 4/3y^2+(4/3y^2)^2`

`=x^2+8/3xy^2+16/9y^4`

`9)`

`(2x^2+5/3y)^2`

`=(2x^2)^2+2.2x^2 . 5/3y+(5/3y)^2`

`=4x^4+20/3x^2y+25/9y^2`

`10)`

`(1/2-x)^3`

`=(1/2)^3-3.(1/2)^2 . x+3. 1/2 .x^2-x^3`

`=1/8-3/4x+3/2x^2-x^3`

`=1/8+(-3/4x)+3/2x^2+(-x^3)`