5.26 In enzyme kinetics, two alternative models relating y to x1 and x2 are specified as follows, where V , κ1, κ2 and κ3 are parameters.

(i)

y = V x1

κ1



1 + x2

κ2



+ x1



1 + x2

κ3



,

(ii)

y = V x1

κ1



1 + x2

κ2



+ x1

.

Identify which non-regular problem results when we compare these two models.