Question

what is the derivative of rad(cos^3x)?

Answer 1

what is rad?

Answer 2

radical

Answer 3

\[\sqrt{\cos ^{3}x}\]

Answer 4

the derivative of the inside is (.5)(3(-sinx)^2)^-1

Answer 5

I mean the derivative of the whole thing

Answer 6

on the outside is it -1/2?

Answer 7

wait no type.. it is (.5) ((-sinx)(3(cosx)^2))^-1/2

Answer 8

The constant term is -1/2 and the whole second part should be in the denomenator

Answer 9

okay so when you chan the radical, you do the derivative of the cos. and in finding the derivative of cos, you have to chain it again?

Answer 10

yes its a whole bunch of chains.

Answer 11

haha, okay. are you taking ap test?

Answer 12

http://www.wolframalpha.com/

Answer 13

Ya i am.. taking BC calc

Answer 14

did you take the AB last year?

Answer 15

the test i mean

Answer 16

No i just flexed it.

Answer 17

I learned all of this in like middle school, and then now I'm just testing out of it so I can take college next year. calc 3 = fun

Answer 18

haha. cool. i'll take the AB test next week. =] good luck with everything !

Answer 19

yep you too.

Answer 20

Ya I was wrong again.. use http://www.wolframalpha.com/input/?i=%28cos^3x%29^.5

Answer 21

i didn't know you could use u sub for derivatives...

Answer 22

They use it for the chain rule, but most of the time you don't see it.,