Question

Tính nhanh 
a) 2022² - 2.4044 + 4 
b) 8-12x+6²-x³ tại x= -2

Answer 1

\(a,=\left(2022-2\right)^2\\ =\left(2020\right)^2=4080400\\ b,=\left(2-x\right)^3\\ =\left(2-\left(-2\right)\right)^3\\ =4^3=64\)

Answer 2

a: \(=\left(2022-2\right)^2=2020^2\)

b: \(=\left(2-x\right)^3=\left(2+2\right)^3=4^3=64\)

Answer 3

`(a):`

`2022^{2}-2.4044+4`

`=2022^{2}-2.2022.2+2^{2}`

`=(2022-2)^{2}`

`=2020^{2}`

`=4080400`

`(b):\  8-12x+6x^{2}-x^{3}`

`=2^{3}-3.2^{2}.x+3.2.x^{2}-x^{3}`

`=(2-x)^{3}`

Với `x=-2` :

`[2-(-2)]^{3}=4^{3}=64`