Question

Tính (khai triển hằng đẳng thức)
\(2) (x+3)^2\)
\(5) (x-6)^2\)
\(8) (3x+1)^2\)
\(11) (3x+2)^2\)
\(14) (x+2y)^2\)
\(17) (3x-2y)^2\)

Answer 1

`2)(x+3)^2=x^2+6x+9`

 `->HĐT` số `1`

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`5)(x-6)^2=x^2-12x+36`

 `->HĐT` số `2`

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`8)(3x+1)^2=9x^2+6x+1`

 `->HĐT` số `1`

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`11)(3x+2)^2=9x^2+12x+4`

 `->HĐT` số `1`

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`14)(x+2y)^2=x^2+4xy+4y^2`

 `->HĐT` số `1`

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`17)(3x-2y)^2=9x^2-12xy+4y^2`

 `->HĐT` số `2`

Answer 2

`(x+3)^2 = x^2 +6x+9`

`(x-6)^2 = x^2 -2.x.6 + 6^2 = x^2 - 12x +36`

`(3x+1)^2 = 9x^2 +6x+1`

`(3x+2)^2 = 9x^2 +12x+4`

`(x+2y)^2 = x^2 + 4xy + 4y^2`

`(3x-2y)^2 = 9x^2 -12xy+4y^2`