Question

If f(t)=(5t-7/t)^4/7,find prime of f(x) using chain rule

Answer 1

use power rule first

Answer 2

How do I do that?

Answer 3

\[\huge \frac{d}{dx} x^n \implies nx^{n-1}\]

Answer 4

ok. So it would turn to (4/7)(5t-7/t)^-3/7

Answer 5

wait yeah sorry

Answer 6

now take the derivative of 5t - 7

Answer 7

That would be just 5 right

Answer 8

wait... it's 5t - 7/t

Answer 9

so it's not just 5

Answer 10

5-7?

Answer 11

no.. derivative of 7/t is not 7

Answer 12

\[\huge \frac 7t \implies 7t^{-1}\]
use power rule on that

Answer 13

Oh yeah because it come up so you have to make it in to a negative

Answer 14

yes

Answer 15

so we are at (4/7) (5-7t^-1)^-3/7
do we multiply the (4/7)?

Answer 16

you still have to derive 5t - 7/t...

Answer 17

but wouldn't that be the second prime of f(x)
?

Answer 18

it's chain rule

Answer 19

\[\Large \frac{d}{dx} f(x)^n \implies n\cdot f(x) ^{n-1} f'(x)\]

Answer 20

if you want to go algebra

Answer 21

(4/7)(5-7t^-1)(5)

Answer 22

we've been over this.. the derivative of 5t - 7/t is not 5

Answer 23

how about i show you how to do the chain rule....it seems you're confused about it...

Answer 24

\[\huge \frac d{da} (a^2 + 3a - 4)^3\]
\[\huge \implies 3(a^2 + 3a - 4)^{3-1} \cdot \frac d{da} (a^2 + 3a - 4)\]
\[\huge \implies 3(a^2 + 3a - 4)^2 \cdot (2a + 3)\]
\[\huge \implies (6a + 9)(a^2 + 3a - 4)^2\]
got it now?