What is the Product Rule?
The product rule is used when differentiating two functions that are multiplied by eachother. The formula for the product rule is:
U (dv/dx) + V (du/dx) where 'dv/dx' is the differential of the function, V.
For example:
y=(x2 + 3)(2x +5) .... we label the first bracket as U and the second as V.
To find dy/dx we apply the product rule:
U= (x2 + 3) du/dv= 2x as we differentiate any x variable by bringing the power down to the front and then minusing one from the power)
V= (2x+5) dv/dx= 2
Therefore, applying the product rule gives:
(x2 +3)2 + 2x(2x+5) = 4x2 + 10x + 6
AW
