Question

how do I find the slope of the curve at x = -9. when Let f(x)=5 x^2 + 2/x^2. (this new to me)

Answer 1

I first find the f'(x) = 10x+1/-2x right ?

Answer 2

or dy/dx= 10x-4x^-3 right

Answer 3

then I plug in for x=-9

Answer 4

yes correct

Answer 5

then it is 10(-9)-4(-9)^3=

Answer 6

-90-2916=

Answer 7

oh the exponent is neg, so you are dividing by 9^3

Answer 8

wait is ot 10(-9)-4(-9)^-3

Answer 9

that is correct

--> -90 +4/9^3

Answer 10

(-9)^-3 = -1/9^3

Answer 11

wait im lost

Answer 12

so its -90-1/9^3

Answer 13

you did something wrong when you wrote ...-90 -2916

property of neg exponents: x^-n = 1/x^n right

Answer 14

yes

Answer 15

10(-9) - 4(-9)^-3

= -90 +4/9^3

= -90 +4/729

= -89.9945

Answer 16

oh ok divide 4/729

Answer 17

I was multiplying 4(9)^3

Answer 18

:)

Answer 19

is that the approximate or exact answer?

Answer 20

how can i find the exact number because they want me to find the exact anwser

Answer 21

nevermind I found it thanx