Question

Let f(t)=4 t^2 + 4/t^2.

Find the slope of the curve at t = -3. Give both exact (symbolic) and approximate (numeric) answers.

Answer 1

df/dt=8t-2/t^2
so t=-3 => 8*(-3)-2/(-3)^2
-24-2/9 !

Answer 2

so, just do the calculations and I have the answer?

Answer 3

yup! ps: you know derivatives right?

Answer 4

yeah, just use the power rule right?

Answer 5

yes, derivatives is a simple way ;)

Answer 6

but how do i use it in this problem?

Answer 7

the derivatives is a function that describe the slope in every part of your main function, also in the -3 point ;)

Answer 8

ok can you give me the equation? or formula?

Answer 9

for calculate the derivatives?

Answer 10

no, the equation to solve this problem

Answer 11

I wrote it, df/dt is the derivatives of f(t) in t variables, maybe you like more f'(t)=8t-2/t^2 ?

Answer 12

*more like

Answer 13

I know you gave 8(-3) -2/-3^2

then -24-2/9

Answer 14

but what do I do after that?

Answer 15

ehm, sum XD I was lazy to sum the numbers, -218/9 is your slope

Answer 16

i Dont know if that's right bcause when I plug that in to the system im on it's saying its wrong

Answer 17

douch! maybe I've failed the derivatives!

Answer 18

yup I failed, currect derivatives is: f'(t)=8t-8/t^3 sorry man

Answer 19

hold on but the eqaution is f(t)=4 t^2 + 4/t^2.

Answer 20

yes