differentiate the function

Question

 y=cos(4x^2+3)

Answer 1

Jessica,

 

Here you can use the substitution method where you assign a function u and use the property that dy/dx=(dy/du)*(du/dx).  In this case we let u=4x^2+3 and y=cos(u).

Then dy/du=-sin u and du/dx=8x, making dy/dx=-8x sin (4x^2+3)

(Don't forget to plug u back in!)

 

Hope that helps!