If f(x)=x2f(x) = x^2f(x)=x2 for x≥0x \geq 0x≥0 and f(x)=−xf(x) = -xf(x)=−x for x<0x < 0x<0, is f(x)f(x)f(x) injective?
Yes
No
Only for x>0x > 0x>0
Only for x<0x < 0x<0