Question

find ther derivative of: f(x)=4/cotx + 6x^2
i have: -4/csc^2(x) + 12x

is that right?

Answer 1

4/cot x= 4 tanx

Answer 2

and the derivative of 4 tanx = 4 sec^2 x

Answer 3

do u know the derivative of 1/x?

Answer 4

i meant sec not csc

Answer 5

2 root x

Answer 6

or -x^2

Answer 7

or somthing

Answer 8

derivative of 1/x = -1/x^2

Answer 9

but how did it come?

Answer 10

okay but the derivative of cot = -csc2x

Answer 11

yes

Answer 12

but u have to find the derivative of 4/cot x

Answer 13

just wait...derivative of x is 1..right?

Answer 14

yes

Answer 15

den will the derivative of 1/x be also 1?

Answer 16

no

Answer 17

the derivative of 1/x = -1/x^2

Answer 18

ok...so derivative of cot x is - cosec^2 x
den derivative of 1/cot x is - 1/ cosec^2x?

Answer 19

r u getting..what do i mean?

Answer 20

i know all my derivatives and my trig derivatives,
like i dont understand what you're trying to say here.

Answer 21

ok

Answer 22

i just want to know why my answer isnt right and what the right answer is.

Answer 23

right answer is 4 sec^2 x+12 x

Answer 24

why

Answer 25

yep confirmed askash123 is right !

Answer 26

have u ever encountered this
d (u/v) / dx= { u' v - u v'}/ v^2
where u and v are functions of x
and u' and v' are the derivative of u and v wrt x respectively

Answer 27

see u have to find the derivative of 4/cotx...right?

Answer 28

and u know the formula for the derivative of cotx?

Answer 29

i.e. d(cot x)/ dx= - cosec^2 x

Answer 30

and u r using this in finding out the derivative of 1/ cotx

Answer 31

so why i asked u...d(1/x)/ x= ?

Answer 32

it should be 1 because the derivative of x is 1 so d(1/x)/ dx=1

Answer 33

the derivative of x is 1
so d(1/x)/ dx=1

Answer 34

u agree that derivative of 1/x is -1/x^2
but how did it come?