$\cos\left(2x\right)$  

 $-2x\cos\left(x^2+4\right)$  

 $\cos\left(x^2-4\right)$  

 $2x\cos\left(x^2+4\right)$  

A. When there is more than one variable

B. When there is a whole equation to a certain power ((u)^2)

C. When dealing with a trig function of an equation (sin(U))

D. All of the above

E. Answers B and C only

When dealing with more than one variable

When it is difficult to solve for a variable before differentiating

all of the above

none of the above

 $-\frac{4}{\sqrt{1-8z}}$  

 $\frac{1}{2\sqrt{1-8z}}$  

 $\sqrt{-8}$  

 $\frac{4}{\sqrt{1-8z}}$  

 $\frac{1}{\left(\cos\left(t^2+4\right)\right)^2}$  

 $-\frac{4t\cos\left(t^2+4\right)}{\left(\sin\left(t^2+4\right)\right)^3}$  

 $\frac{1}{4t\sin\left(t^2+4\right)\cos\left(t^2+4\right)}$  

 $-\frac{2}{\sin\left(t^2+4\right)}$  

 $\left(20x^2+40x\right)e^{\left(x^2+2x-1\right)}$  

 $\left(40x+40\right)e^{\left(x^2+2x\right)}$  

 $\left(20\right)e^{\left(2x+2\right)}$  

 $\left(40x+40\right)e^{\left(2x+2\right)}$  

-4/7

12

-9

9

 $\frac{1}{x\ln2x}$  

 $\frac{1}{x}$  

 $\frac{1}{2x}$  

 $\frac{1}{\ln2x}$  

 $-\frac{3}{\left(x^3-x^2+3\right)^2\left(9x^2-6x\right)}$  

 $\frac{9x\left(3x-2\right)}{\left(x^3-x^2+3\right)^2}$  

 $\frac{\left(3x^2-2x\right)}{\left(x^3-x^2+3\right)^4}$  

 $\frac{\left(27x^2-18x\right)}{\left(x^3-x^2+3\right)^4}$  

 $y=-\frac{x}{2}+2$  

 $y-1=-\frac{1}{2}\left(x-2\right)$  

 $\frac{dy}{dx}=-\frac{1}{2}$ 

 $y-1=-\frac{1}{12}\left(x-2\right)$  

 $\frac{1}{2}\tan2y\tan x$  

 $\frac{1}{2}\cot2y\cot x$  

 $-2\tan2y\tan x$  

 $\frac{5}{y}$  

 $\frac{10}{y}$  

 $\frac{y^2}{5}$  

 $\frac{y^2}{10}$