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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Find f'(x) (the derivative of f(x)) if f(x) = 7x^3 - 2x^2 + 4x - 5.

21x^2 - 4x + 4

The integral of 3x^2 - 4x + 1 equals x^3 - 2x^2 + x. Is this always correct?

No

Find dy/dx if y = e^a and a is constant.

0

If f(x) = x (ln x), find f'(x).

1 + ln x

If the velocity of a particle at time t is represented by the equation v(t) = 8t + 2, find the position of the particle at time 3 if the position at time 0 is 0.

42

An object is in freefall. It remains in freefall for 5 seconds before it hits the ground. How high was the object when it first started falling if its starting velocity was 0? (Acceleration due to gravity is -9.8 meters/second^2).

122.5m

If f(x) = (sin x)/x, what is the limit of the function as x approaches zero?

1

Find the area of the region bounded by the graphs of y = x^2; x = 0; x = 2; and the x axis.

8/3

If f(x) = e^x, the integral of f(x) always equals the derivative of f(x).

no

If f(x) = x^3 - 2x^2 + 4x + 1, how many inflection points does this graph have?

1

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

If you guys could check them...Much appreciated.

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**zetafunc.****Guest**

Those all look correct to me.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

Hi;

I agree with the first six.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Well, this was relatively simple. Anyways, thanks a lot.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

Hi;

7 and 8 are also good.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Thank-you. Much appreciated.

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**zetafunc.****Guest**

May I ask what course this is for? It seems like your work is a mixture of calculus and mechanics -- do you do any statistics?

**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Not statistics. I am taking a mechanical engineering course along with a physics course.

*Last edited by Shivamcoder3013 (2012-11-02 01:25:19)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

Hi;

9,10 and 11 all fine by me. Very good!

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Thank-you, but these were extremely easy. Doesn't deserve a "very good"!

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

Are there any really easy problems? You can always make a mistake. Last mistake I made I did not copy the answer correctly after I found it!

**In mathematics, you don't understand things. You just get used to them.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Ha! But these are just review questions.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

Some people when faced with easy questions or tasks make mistakes. In competition we have a name for people like that.

**In mathematics, you don't understand things. You just get used to them.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Meh. What is the name?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

Loser.

When someone is capable of beating weaker opponents consistently we say he is a good fishkiller. Same thing with questions. Your success in life is going to be determined by how you deal with the easy stuff. That is where you show your concentration and consistency.

**In mathematics, you don't understand things. You just get used to them.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Fishkiller. What about beating someone older and stronger then you? Lion-Killer?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

School teaches you about winning the big ones and being a hero. I know many people who are capable of slaying a dragon but then they lose to a much weaker obstacle. They lack consistency, they lack focus. They can not succeed.

**In mathematics, you don't understand things. You just get used to them.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Then there are the occassional few who take advantage of school and retain their knowledge forever (i.e. a guy named bobbym).

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

The two best mathematicians in my opinion on this site are both self taught!

**In mathematics, you don't understand things. You just get used to them.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Those being? You and MIF? In terms of the few best on this site (in my preference): You, MIF, Stefy. Self-taught or not.... I would consider myself self-taught, as I elarn nothing from school (as of now). However, it is challenging. Visiting calculus-tutoring sites when I was 9...What a bother!

*Last edited by Shivamcoder3013 (2012-11-02 02:23:36)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

Certainly not me. I have carelessly said something I should not have and apologize for mentioning those two people.

**In mathematics, you don't understand things. You just get used to them.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Always be meticulous in your actions! But how is a bad thing? Mind discolsing those two sacred names of master mathematicians on this very forum?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,821

If I mention them I insult others who may feel left out. There are many talented people here. The best part is most of them do not know it!

**In mathematics, you don't understand things. You just get used to them.**

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Anyone smart enough to think that they deserve to be held in great self-esteem by you are smart enough to honour the skils of others.

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