Solve, correct to 2 decimal places, the equation cot(2x)=3 for 0°<x<180°

To start, we use the inverse trigonometric formulae to convert the 'cot' function into a 'tan' function: cot(2x)=1/(tan(2x))=3 Inverting this gives: tan(2x)=1/3 2x=arctan(1/3)=18.43°or (180+18.43)° Therfore dividing by 2 gives the solutions as: x= 9.22° or 99.22°