By first expanding the brackets, differentiate the equation: y=(4x^4 + 3x)(2x^2 - 9)

In this case the question has given you a clue as to the order that you solve the question. So, first we need to expand the brackets, multiplying each term by one another to get; y=8x^6 - 36x^4 + 6x^3 - 27x.
We then need to differentiate the equation we have found by multiplying each coefficient of x by the power of each x term, so 6x^2 and then subtracting 1 from each power of x. For example 6x^3 would become 18x^2 (6 x 3 =18, 3 - 1=2)
We then reach the final answer of dy/dx= 48x^5 - 144x^3 + 18x^2 - 27