Question

1) (x+1)³

2) (x+2)³

3) (x+3)3

Answer 1

`1)`

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

`= x^3 + 3x^2 + 3x +1`

`2)`

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

`= x^3 + 6x^2 + 12x+8`

`3)`

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

`= x^3 + 9x^2 + 27x + 27`

`--------------`

`@ ` áp dụng HĐT số 4`

Answer 2

1.(x+1)^3

=x^3+3x^2+3x+1

2.(x+2)^3

=3x+63.

3.(x+3)^3

=3x+9

Answer 3

1.\(\left(x+1\right)^3=x^3+3x^21+3x1^2+1^3=x^3+3x^2+\) \(3x+1.\)

2.\(\left(x+2\right)^3=x^3+3x^22+3x2^2+2^3=x^3+6x^2+\)\(12x+8.\)

3.\(\left(x+3\right)^3=x^3+3x^23+3x3^2+3^3=x^3+9x^2+\)\(27x+27.\)

Answer 4