a.\(D=R\)\(f\left(-x\right)=\left(-x\right)^2+4.\left(-x\right)-2=x^2-4x-2\)Hàm ko chẵn ko lẻb.\(D=R\)\(f\left(-x\right)=\left|-x+2\right|-\left|-x-2\right|=\left|x-2\right|-\left|x+2\right|=-\left(\left|x+2\right|-\left|x-2\right|\right)=-f\left(x\right)\)Hàm lẻc.\(D=R\backslash\left\{0\right\}\) là miền đối xứng\(f\left(-x\right)=\dfrac{\left(-x\right)^3+6}{-x}=\dfrac{-x^3+6}{-x}=\dfrac{x^3-6}{x}\)Hàm ko chẵn ko lẻd.\(D=R\backslash\left\{0\right\}\) là miền đối xứng\(f\left(-x\right)=\dfrac{-x}{\left|-x\right|}=-\dfrac{x}{\left|x\right|}=-f\left(x\right)\)Hàm lẻCâu trả lời: a.\(D=R\)\(f\left(-x\right)=\left(-x\right)^2+4.\left(-x\right)-2=x^2-4x-2\)Hàm ko chẵn ko lẻb.\(D=R\)\(f\left(-x\right)=\left|-x+2\right|-\left|-x-2\right|=\left|x-2\right|-\left|x+2\right|=-\left(\left|x+2\right|-\left|x-2\right|\right)=-f\left(x\right)\)Hàm lẻc.\(D=R\backslash\left\{0\right\}\) là miền đối xứng\(f\left(-x\right)=\dfrac{\left(-x\right)^3+6}{-x}=\dfrac{-x^3+6}{-x}=\dfrac{x^3-6}{x}\)Hàm ko chẵn ko lẻd.\(D=R\backslash\left\{0\right\}\) là miền đối xứng\(f\left(-x\right)=\dfrac{-x}{\left|-x\right|}=-\dfrac{x}{\left|x\right|}=-f\left(x\right)\)Hàm lẻ