Question

Xét tính chẵn lẻ của hàm số

a) y=\(\dfrac{x^5-x}{\sqrt{x^2+|x|}}\)

b)y=\((|9-2x|-|9+2x|)(x-5x^3)\)

c)y=\(\dfrac{|3-x|-|3+x|}{x^4+1}\)

d)y=\(\dfrac{|x+1|+|x-1|}{|x+1|-|x-1|}\)

Answer 1

a: \(f\left(-x\right)=\dfrac{-x^5+x}{\sqrt{\left(-x\right)^2+\left|-x\right|}}=-f\left(x\right)\)

=>f(x) lẻ

b: \(f\left(-x\right)=\left(\left|9+2x\right|-\left|9-2x\right|\right)\left(-x+5x^3\right)\)

\(=f\left(x\right)\)

=>f(x) chẵn

c: \(f\left(-x\right)=\dfrac{\left|3+x\right|-\left|3-x\right|}{\left(-x\right)^4+1}=-f\left(x\right)\)

=>f(x) lẻ