Question

Find the derivative of f(x) = 5 divided by x at x = -1.

Answer 1

use quotient rule then substitute the value at x=-1

Answer 2

I dont understand at all

Answer 3

\[ \frac{5}{x}=5x^{-1}\] and use the power rule, it's easier than using the quotient rule.

Answer 4

is it 5?

Answer 5

There's something missing

Answer 6

\[ \frac{d}{dx}5x^{-1}=5(-1)x^{-2}\], now evaluate at \(x=-1\)

Answer 7

nothing is easier than anything
it is a matter of technique

Answer 8

Well I meant easier in the sense that you perform less steps, and you don't have to worry about remembering an additional rule if you don't want. (All quotients can technically be differentiated with the product + chain rule)

Answer 9

haaaaaa?

Answer 10

For example:
\[ \frac{4x+1}{2x^2+2}=(4x+1)(2x^2+2)^{-1}\]

Answer 11

laughing out loud I am messing with you. Again, it is a matter of technique and whatever the person is proficient at doing

Answer 12

^true

Answer 13

well you've just set yourself up, young man
I can do that fast in quotient rule than you can in product

Answer 14

I suppose, but again, whatever technique suits the person. And I think the power rule above is faster than using the quotient rule :P