this video covers variation of parameters and cauchy euler and various integration techniques like trigonometric sub timestamps 1:00 variation 1 6:05 variation2 13:20 variation 3x3 matrix 20:05 cauchy1 21:58 cauchy2 23:56 non homogeneous cauchy 32:11 trig sub for the full playlist • ODE's hashtags #ordinarydifferentialequations #maths #math3 #trignometricidentities #euler