When calculating a question with a double integral question between two different ranges which range relates to which integration variable.

When doing double integration with two arbitrary variables, for example 'x' and 'y' look at the Integration on the inside and integrate the function between the given range. For example if the integrand is to be integrated in terms of x and then y written 'dxdy' this means you integrate the function with respect to x first between the inner range, and then integrate the integrand with respect to y between the outermost range.