Question

Calculus: Find the derivative.
y=cos2x/x^3

Answer 1

\[y \frac{ \cos2x }{ x ^{3} }\]

Answer 2

\[y=\cos2x * x ^{-3}\]

Answer 3

Nw Differemtiate

Answer 4

\[y =\frac{ \cos 2x }{ x ^{3} }\]

Answer 5

wouldn't divison rule be simpler?

Answer 6

Ok...Product oR Quotient Rule...

Answer 7

The negative exponent is all good to use the product rule byt it is not necessary! You could use the quotient rulw! Much easier!

Answer 8

ill use division rule :)

Answer 9

Do you know how to use the quotient rule @lilfayfay ?

Answer 10

yepp but i think division rulewould be much easier :)

Answer 11

Same thing!!

Answer 12

can we use division rule pls :)

Answer 13

\[\frac{ dy }{ dx }=\frac{ f \prime(x)g(x)-f(x)g \prime(x) }{ [g(x)]^{2} }\]if\[y =\frac{ f(x) }{ g(x) }\]Call it the quotient rule or call it the division rule. @lilfayfay they are the same thing!!

Answer 14

oh ok lol

Answer 15

so i worked out the problem and i almost got the same thing
the answer is \[\frac{ -2xsin2x-3\cos2x }{ x ^{4} }\]

Answer 16

OK let's do this in baby steps.

Step 1: Tell me the following:

i). f(x) = ?
ii). f '(x) = ?
iii). g(x) = ?
iv). g'(x) = ?
v). [g(x)]² = ?

Answer 17

OH Is that your final answer? LOL @lilfayfay

Answer 18

yeah.. :P

Answer 19

sorry its late here for me kinda sleepy =w=

Answer 20

OH yeah your final answer is correct. I thought you were showing me the first step. Sorry.

Answer 21

no, but that wasn't my final answer, that was the answer I got from the back; I got a similar answer but a little bit off so can you tell me how you did urs pls? ^^

Answer 22

I'm am actually a teacher LOL. I don't give out answers. You show your work and I can tell you what you did right orr start by answering my question I asked.

Answer 23

Why did you delete it while I was checking?

Answer 24

OK you really want me to write out the steps?