Partial derivative chain rule :'/. I will attach an image of the question and my attempt.

Question

anonymous · Answer

attachment

anonymous · Answer

attachment

anonymous · Answer

oh oops... I just realized I was entering x's haha.

anonymous · Answer

I'm an idiot. I accidentally wrote sec(x)tan(x) instead of sec(t)tan(t) Dx.

anonymous · Answer

also, I accidentally dropped an addition sign, but I got it right now :). If anyone wants free points, just write a reply and I'll mark it as the best answer xD.

astrophysics · Answer

:) always lovely seeing people figuring out their own mistakes hehe, well done! Do not medal, I just like the post!

anonymous · Answer

Thank you. Math is usually pretty painful for me but the persistence pays off eventually... hopefully :p

astrophysics · Answer

Haha, you're not alone!