Find the given derivative by finding the first few derivatives and observing the pattern that occurs.
d87/dx87 (sin x)

Question

Find the given derivative by finding the first few derivatives and observing the pattern that occurs. 
d87/dx87 (sin x)

anonymous · Answer

Any help with this? bit lost

anonymous · Answer

Do the first 5 derivatives.

anonymous · Answer

They key here is that after every 4 derivatives, you return to your original function.

anonymous · Answer

So you take out the first 84 derivatives, since 84 is divisible by 4, and then are left with doing just 3 differentiations.

anonymous · Answer

I'm really lost. Anyone has the answer?

anonymous · Answer

This is due in half an hour and Ive been at it for 2 hours and I don't get it.

anonymous · Answer

Dude, just take the derivative of sin(x)

anonymous · Answer

Then take the derivative of that.

anonymous · Answer

thats -sin(x)

Thats not the answer.

anonymous · Answer

oh

anonymous · Answer

so is the answer -cos(x) and the 84 doesn't actually matter?

anonymous · Answer

Indeed. Thank you good sir. I'd appreciate less socratic method in the future, but here's your medal