YAMT

[jhayx7]

Ok, I am stuck on this and I had someone explain this to me and I still don't get it so I hope someone else here can explain it in a manner that my brain will process.

I am using the Product Rule and I am trying to find the derivative of this function:

f(x)=(x^2-5x+2)(x-2/x)

Break it down:

f(x)=(x^2-5x+2) d/dx (x-2/x) + (x-2/x) d/dx (x^2-5x+2)

Now I am stuck. I do not know how to find (x-2/x).

If someone could help or nudge me in the right direction. Thanks!



Do your own homework and check your attitude at the door.
AnandTech Moderator

 

[SmoochyTX]

Don't you mean YAHomeworkT?

 

[jhayx7]

Originally posted by: SmoochyTX
Don't you mean YAHomeworkT?

This is for my onilne calculus class for college.

I purchased the student solution manual because I can usually figure the problems out on my own but I don't know how they came up with the solution on this one. They are doing something that was not explained earlier.

 

[SmoochyTX]

Originally posted by: jhayx7

Originally posted by: SmoochyTX
Don't you mean YAHomeworkT?

This is for my onilne calculus class for college.

I purchased the student solution manual because I can usually figure the problems out on my own but I don't know how they came up with the solution on this one. They are doing something that was not explained earlier.

So then it's homework.

 

[jhayx7]

Originally posted by: SmoochyTX

Originally posted by: jhayx7

Originally posted by: SmoochyTX
Don't you mean YAHomeworkT?

This is for my onilne calculus class for college.

I purchased the student solution manual because I can usually figure the problems out on my own but I don't know how they came up with the solution on this one. They are doing something that was not explained earlier.

So then it's homework.

And?

 

[Sukhoi]

Just expand it out and do it term by term.

And if I'm not mistaken d/dx of (x-2/x) is 1+2/(x^2).

 

[SmoochyTX]

Originally posted by: jhayx7

Originally posted by: SmoochyTX

Originally posted by: jhayx7

Originally posted by: SmoochyTX
Don't you mean YAHomeworkT?

This is for my onilne calculus class for college.

I purchased the student solution manual because I can usually figure the problems out on my own but I don't know how they came up with the solution on this one. They are doing something that was not explained earlier.

So then it's homework.

And?

It's another effin homework thread. Enough said.

 

[jhayx7]

Originally posted by: Sukhoi
Just expand it out and do it term by term.

f(x)=(x^2-5x+2) d/dx (x-2/x)

This part has me stumped. It breaks down as:

(x^2-5x+2)(x^2+2)/x^2

I don't know how they got (x^2+2)/x^2.


Math is a product of the devil.

 

[SonnyDaze]

Topic Title: YAMT
Topic Summary: My first post on this subject so bite me

Thought someone posted a YAM(an)Thread.

 

[JujuFish]

Originally posted by: jhayx7

Originally posted by: Sukhoi
Just expand it out and do it term by term.

f(x)=(x^2-5x+2) d/dx (x-2/x)

This part has me stumped. It breaks down as:

(x^2-5x+2)(x^2+2)/x^2

I don't know how they got (x^2+2)/x^2.


Math is a product of the devil.

1+2/x^2 = (x^2+2)/x^2

 

[Ophir]

Originally posted by: jhayx7

Originally posted by: Sukhoi
Just expand it out and do it term by term.

f(x)=(x^2-5x+2) d/dx (x-2/x)

This part has me stumped. It breaks down as:

(x^2-5x+2)(x^2+2)/x^2

I don't know how they got (x^2+2)/x^2.


Math is a product of the devil.

Why don't you expand it out before taking the derivative?

f(x)=(x^2-5x+2)(x-2/x)
= (x^2-5x+2)(x)-(x^2-5x+2)(2/x)
= x^3-5x^2+2x-2x+10-4/x
= x^3-5x^2+10-4/x

You should be able to solve that.