Simple derivative question please help

john.johnson

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Im a little confused to a derivative question I have.

y=6x^-6-3^-3

Im confused about y=
Im used to finding the derivative d/dx
Is this the same thing?
My answer is -36/x^7

Sorry if I'm not making sense I'm new to calc.
 
Im a little confused to a derivative question I have.

y=6x^-6-3^-3

Im confused about y=
Im used to finding the derivative d/dx
Is this the same thing?
My answer is -36/x^7

Sorry if I'm not making sense I'm new to calc.

If your problem is:

y = 6x6  33\displaystyle \displaystyle{y \ = \ 6x^{-6} \ - \ 3^{-3}}

then indeed

dydx = 36x7\displaystyle \displaystyle{\frac{dy}{dx} \ = \ -\frac{36}{x^7}}
 
Im a little confused to a derivative question I have.

y=6x^-6-3^-3

Im confused about y=
Im used to finding the derivative d/dx
Is this the same thing?
My answer is -36/x^7

Sorry if I'm not making sense I'm new to calc.
y= 6x^(-6)- 3^(-3) is the same as y= 6/x^6- 1/27

Its derivative if dy/dx= 6(-6)x^(-7)- 0= -36x^(-7) which is the same as dy/dx= -36/x^7
 
Im a little confused to a derivative question I have.

y=6x^-6-3^-3

Im confused about y=
Im used to finding the derivative d/dx
Do you mean that you're used to taking the derivative of f(x), so you've been doing df/fx rather than dy/dx?

Is this the same thing?
If you are asking if y is the same as its derivative, dy/dx, then the answer is "no". If you are asking if y is the same as f(x), then the answer is "yes".

My answer is -36/x^7
If you mean that your answer for the derivative is "dy/dx =" your expression, then you are correct. ;)
 
If this was on a test would it be

9/x^4-36/x^7

or just

-36/x^7

Where is that coming from?

Is your problem:


y = 6x6  3x3\displaystyle \displaystyle{y \ = \ 6x^{-6} \ - \ 3x^{-3}}
 
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Im a little confused to a derivative question I have.

> > > y=6x^-6-3^-3 < < <

Im confused about y=
Im used to finding the derivative d/dx
Is this the same thing?
My answer is -36/x^7

john.johnson, look at the quote box from your first post.

You made a typo, didn't you?


It should have been the equivalent of  y =6x63x3,  correct?\displaystyle \ y \ = 6x^{-6} - 3x^{-3}, \ \ correct?
 
john.johnson, look at the quote box from your first post.

You made a typo, didn't you?


It should have been the equivalent of  y =6x63x3,  correct?\displaystyle \ y \ = 6x^{-6} - 3x^{-3}, \ \ correct?

Correct I did make a typo!
 
Im a little confused to a derivative question I have.

y=6x^-6-3^-3

Im confused about y=
Im used to finding the derivative d/dx
Is this the same thing?
My answer is -36/x^7

Sorry if I'm not making sense I'm new to calc.

1. The original equation, y=6x^-6-3^-3 is just a curve.

2. The Y here in this specific context means the same as F(x).
- When you plug in a value for X, and solve the original equation, you get a Y point as a return value. This is the same thing with linear equations in algebra. That's why it is Y=
since the equation represents a Y value in the Cartesian plane. Plug in X get a Y back

3. When you "take the derivative" of the original equation, y=6x^-6-3^-3 ... You are creating a new equation that will be utilized to obtain a
slope of the "tangent line" on any point on the curve. The new equation (derivative) is represented by F'(x) = Technically y can be used for this too.

- In algebra with a linear equation (line). The slope is the same for every X value you plugin, the slope is always going to be a fixed angle in the XY plane (rise over run).
recall y=mx+b where M is the slope

-With curves such as y=6x^-6-3^-3 the slope is different at every X point. Each tiny interval along the curve is represented by DX

- When you plug in a value into this new equation -36/x^7 (which is called the derivative) , you get a Y point as a return value, but now the Y return from this new equation represents the
slope at that point (tangent).

-DY/DX is the rate of change (or difference) for each tiny slice along the curve. In this context, each time you plugin in a new X into the derivative formula y=-36/x^7, you a get different Y out. The Y is just a unique slope value.

Conclusion: All the first derivative is doing is allowing you to calculate the slope (Y) for/at every (X). So just think of Y as the slope and DX as the tiny increment between all these slopes.
The whole reason of finding a derivative of a curve is to create a formula that allows you to calculate a slope for every point along the curve.
 
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