# Math Help - Trigonometric Derivative Question that I'm getting wrong

1. ## Trigonometric Derivative Question that I'm getting wrong

I attached the question in black and the answer in red in the "question & answer.pdf" file. My work is attached in the "mywork.pdf" file.

Can someone point out what I am doing wrong and tell me the appropriate way to go about it?

Any help would be greatly appreciated!
The derivative of $\sec{2\theta}:2\sec{2\theta}\tan{2\theta}$.