(a) Find a power series representation for the function.
I'm struggling on the decomposition of the numerator. This exercise is from chapter 8, section 6 of Th Stewart Calculus book.
You're on a good way because you just simplified the problem in 2-D; then sum the x-components of the system and the y-components of the system by using trigonometry function and these two equations need to be equal to zero. Then that will become more simplier, and then you can find the answer.