Question

Find the slop of a urve y=(x^3)-2x-2 at a point p(2,-2).
How do I solve this?

Answer 1

Just Differentiate it and then put the points

Answer 2

meant curve, not urve

Answer 3

\[y = x^3 -3x -2 \]
\[\frac{dy}{dx} = 3x^2 - 2 \]

Answer 4

Now put the point and you will have the slope

Answer 5

I tried that and thought it was 0. But thats not the answer

Answer 6

\[y' = 3( 2)^2 -2 \]
\[y' = 12-2\]
\[y' =10\]

Answer 7

hmm how'd you get zero?

Answer 8

If \(f(x)\) is a function or some curve then \(f'(x)\) is it's first derivative and \(f'(a)\) is slope of tangetn at point where x co-ordinate is a.

Answer 9

Well my equation isnt the same, I just was trying to figure out how to do it. The real one is y=(x^2)-2x-2. I got somehow 0

Answer 10

tangent *

Answer 11

hmm \[y = x^2 - 2 -2 \]

Answer 12

Just was trying to figure how out how its done. Still nothing. I did a formula you did. Got 6. But thats wrong

Answer 13

\[\frac{dy}{dx} = 2x -2 \]
\[ \frac{dy}{dx} = 4-2=2\]

Answer 14

I will try that. Honestly wish how it works though.. Cant figure it out

Answer 15

I will try that. Honestly wish how it works though.. Cant figure it out

Answer 16

OKay

Answer 17

hmm what's the exact question
curve is \[y = x^2 -2x-2\] right? so that makes \[y' =2x -2 \] now what are the points ?

Answer 18

You got it right with 2. but why? im more worried about the reason. Yes the curve is right

Answer 19

hmm reason you can watch mit ocw lecture 1 for that a very clear explanation

Answer 20

single variable calculus

Answer 21

Thanks I will keep just checking my book

Answer 22

Good Luck : )

Answer 23

So wait how do I find the equation of a tangent line?

Answer 24

hmm for finding that hmm you have slope right ! so the equation becomes y=mx+c
now in this case slope is 2
y = 2x +c
we also know that line passes through (2,-2) so just put in the points in the equation to determine c .
-2 = 2x2 + c
c = -6
y=2x - 6 you have your equation

Answer 25

damn.. I need to figure out how this works. Just dont see it yet