Ask your own question, for FREE!
Mathematics 14 Online
OpenStudy (zenmo):

Find the slope of the equation. Differentiation.

OpenStudy (zenmo):

\[x^4-2x^2-x\]

OpenStudy (zenmo):

Do I keep reducing the equation with differentiation?

OpenStudy (astrophysics):

You can apply power rule

OpenStudy (astrophysics):

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

OpenStudy (solomonzelman):

You want to find the "slope", or rather a "function that generates slope" (the "derivative of the function".) yes, apply the power rule to each term.

OpenStudy (zenmo):

the slope will be 24x when using differentiation rules 3 times?

OpenStudy (solomonzelman):

Why are you differentiating 3 times ?

OpenStudy (solomonzelman):

You only need to take the derivative once for the slope.

OpenStudy (astrophysics):

Yeah, you have to apply it to each term not 3 times

OpenStudy (zenmo):

\[y' = 4x^3+4x-1\]

OpenStudy (astrophysics):

And you're done

OpenStudy (zenmo):

what would be the slope? the entire equation?

OpenStudy (solomonzelman):

If you want to find a slope at a point (say x=2), then plug in 2 for x. \(\color{#000000 }{ \displaystyle f'(x)=4x^3+4x-1 }\) \(\color{#000000 }{ \displaystyle f'(2)=4(2)^3+4(2)-1 =39}\)

OpenStudy (raffle_snaffle):

Only have to differentiate once to find slope/tangent line

OpenStudy (solomonzelman):

So, yes, the entire equation is the slope.

OpenStudy (solomonzelman):

You forgot, it is -4x.

OpenStudy (solomonzelman):

\(\color{#000000 }{ \displaystyle f'(x)=4x^3-4x-1 }\)

OpenStudy (zenmo):

oh the original equation is \[x^4+2x^2-x\]

OpenStudy (solomonzelman):

Oh, ok ...

OpenStudy (zenmo):

In order to find the equation of the tangent line to the curve at the given point ( 1, 2). I would use the point-slope form?

OpenStudy (solomonzelman):

Yes. `Step  1  .` Plug in x=1 into the derivative, to find the slope at x=1. (Since derivative generates/is the slope of the function) `Step  2  .` Plug in the point (1,2) into the point slope form, with the slope from step 1.

OpenStudy (solomonzelman):

I can give you a similar example-problem as well, if you like ...

OpenStudy (zenmo):

so slope m would be \[y'(1) = 4(1)^3+4(1)-1 = 4 + 4 - 1 = 7\]?

OpenStudy (solomonzelman):

Yes, precisely!

OpenStudy (zenmo):

Okay, I got it now. I'm used to finding slopes from equations like y = mx + b. I can handle the rest now. :)

OpenStudy (solomonzelman):

Alrighty ... good luck!

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!