Calculus I Packet nearly complete!!! Just need help with these questions.

(Hi)

Hey everyone! I've been working on this huge packet filled with College Math II and Calculus 1 questions. I'm finished with 82 problems but now I'm stuck on the below few. If you can, please help me out because this is definitely URGENT!

-----------------

**1.** Given $\displaystyle y=2x^2-8$

Find the equation of the TANGENT line I at $\displaystyle x=2$.

-----------------

**2.** Given $\displaystyle y=[f(x)]^2 * [g(x)]^3$

Find $\displaystyle \frac{dy}{dx}$ "symbolically" (in prime notation)

-----------------

**3.** Given the position function $\displaystyle S=\frac{1}{4}t^4$, find the __instantaneous acceleration__ at $\displaystyle t=4sec$

-----------------

**4.** $\displaystyle y=x\sqrt{2x+3}$

Find $\displaystyle \frac{dy}{dx}$

-----------------

**5.** Evaluate $\displaystyle \lim_{\Delta x\to 0} - \frac{4(x+\Delta x)-4y}{\Delta x}$

-----------------

**6.** The function $\displaystyle y = |x+21|$ is NOT differentiable at x=?

-----------------

**7.** Given the position $\displaystyle S(t)=2t+t^2$, where $\displaystyle S$ is in Ft.

Find the instantaneous velocity at $\displaystyle t=3sec$

-----------------

The questions above are the only ones I'm having a tough time with. Please help me! I would greatly appreciate it. :)

You guys are awesome! This site has been a great resource for me for the past 2 years. Keep it up!