Determining Domain and Range of Multivariable Functions _(check correction in description)

in this tutorial we look at how we can determine the domain and range of multivariable functions
range of f( x , y ) = ln | 36 - 4x^2 + 9y^2 | is all real numbers.

[@wakusumbwa5891]

For question (iv) I don't think the range and domain are correct the domain is supposed to be x^2+y^2