Ta có : `P(x)+(3x^2-2)=x^3+3x^2-2x+2022`
`->P(x)= x^3+3x^2-2x+2022 -(3x^2-2)`
`= x^3+3x^2-2x+2022 - 3x^2 +2`
`=x^3 +(3x^2-3x^2) -2x+(2022+2)`
`=x^3 -2x+2024`
\(P\left(x\right)=x^3+3x^2-2x+2022-\left(3x^2-2\right)\\ =x^3+3x^2-2x+2022-3x^2+2\\ =x^3+\left(3x^2-3x^2\right)-2x+\left(2022+2\right)\\ =x^3-2x+2024\)
`P(x)+(3x^2-2)=x^3+3x^2-2x+2022`
`-> P(x)= (x^3+3x^2-2x+2022)-(3x^2-2)`
`= x^3+3x^2-2x+2022-3x^2+2`
`= x^3+(3x^2-3x^2)-2x+(2022+2)`
`= x^3-2x+2024`
Vậy, `P(x)=x^3-2x+2024`
\(P\left(x\right)+\left(3x^2-2\right)=x^3+3x^2-2x+2022\)
\(\Rightarrow P\left(x\right)=x^3+3x^2-2x+2022-\left(3x^2-2\right)\)
\(\Rightarrow P\left(x\right)=x^3+3x^2-2x+2022-3x^2+2\)
\(\Rightarrow P\left(x\right)=x^3+\left(3x^2-3x^2\right)-2x+\left(2022+2\right)\)
\(\Rightarrow P\left(x\right)=x^3-2x+2024\)
Vậy \(P\left(x\right)=x^3-2x+2024\)