Numeracy 2. A function of n variables f(x), where x = ($1, . .., In), is said to be homogeneous of degree k E N if f(tx) = th f(x) for all t E R. For each function below, show it is homogeneous (of some degree k) or give an example to show it is not homogeneous. 1. f (x, y, z) = Vx9+y+ 29 2. f(x, y, z, w) = x2y2 + 22w2 + xyzw 3. f (x, y) = Va2+ yz. rty 4. f(x, y) = es? / (s2 +x? ty?) ds