# Math Help - linear mapping

1. ## linear mapping

f:R^3→R^2 given by f(x,y,z)=f(x-y+z^2,xy)

is f a linear mapping? How do i start this question??
thanx

2. Originally Posted by xixihaha
f:R^3→R^2 given by f(x,y,z)=f(x-y+z^2,xy)

is f a linear mapping? How do i start this question??
thanx
Is it true that: $f(\bold{x} + \bold{y}) = f(\bold{x})+f(\bold{y})$ and $f(a\bold{x}) = af(\bold{x})$
Where $\bold{x} = (x_1,x_2,x_3)$ and $\bold{y} = (y_1,y_2,y_3)$.