Differentiate the following function u = Cos(x3)
u = Cos(x3)
To differentiate this function we will use the chain rule. Firstly we will set x3 to another variable name such as v. So now v = x3 . Lets differentiate this. dv/dx = 3x2
We can now differentiate cos(v) du/dv = -sin(v). Now to complete the chain rule we must do dv/dx*du/dv. Which will be -sin(v)*3x2 = -3x2sin(v). Now we can just put the x3 back in instead of the v and our final answer will be -3x2sin( x3).
