Question

Which of these functions is not a linear function? Why?

f(x)=x-x
f(x)=3x
f(x)=x3
f(x)=23x-2
how am i supposed to know-

Answer 1

f(x)=x3

Explanation:

If you meant f(x)=x3 by f(x)=x^3 then that would be a cubic equation and not linear?