I'm taking an online course so I have no one to give me feedback before I submit my assignments. Can you please tell me what I got wrong and what's wrong about it?

 

 

It's been a few years since I did Calc, but this doesn't look particularly complicated.

 

1 and 2 look good, although you're missing some parentheses in 2b that are important but the math is done as if they're there so it comes out right, and 2c you wrote the limit as x approaches 5 when it should have been 8, but again, you used 8 in the actual math so it came out fine.

 

3a looks good.

 

3b, you should redo. You forgot to bring down the 3(x+h) after multiplying out the rest of that line, so your f(x+h) is missing a big chunk for most of the problem.

 

You also made a couple of small mistakes with a sign and factoring an h out of a 3x later in the problem, so it's probably best just to start it fresh.