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Any kind of mathematics (calculus, analysis, game theory, linear approximation, finite differences, linear regression, linear programming, numerical analysis, probability, statistics, etc.). I also have answered some questions in Physics (mass, momentum, falling bodies), Chemistry (charge, reactions, symbols, molecules), and Biology.
Experience in the area: I have tutored students in all areas of mathematics for over 20 years. Education/Credentials: BSand MS in Mathematics from Oregon State University, where I completed sophomore course in Physics and Chemistry. I received both degrees with high honors. Awards and Honors: I have passed Actuarial tests 100, 110, and 135.
Maybe not a publication, but I have respond to well oveer 3000 questions on the PC. That's around 2,000 in basic math and 1,000 in advanced math.
I aquired well over 40 hours of upper division courses. This was well over the number that were required. I graduated with honors in both my BS and MS degree from Oregon State University. I was allowed to jump into a few junior level courses my sophomore year.
I have been nominated as the expert of the month several times. All of my scores right now are at least a 9.8 average (out of 10).
My past clients have been students at OSU, students at the college in South Seattle, referals from a company, friends and aquantenances, people from my church, and people like you.
If the digits sum is divisible by 3, so is the number. To test 11, do like this: 407 is divisible by 11 (4 - 0 + 7 = 11, and 11 is divisible by 11). 19,151 is divisible by 11 (1 - 9 + 1 - 5 + 1 = -11, and -11 is divisible by 11); Add odd digits, subtract even digits, and get 11n, the number is divisible by 11.
Doing even more mathematics. Maybe somebody wants me to do this for work, but until then ...
The natural log of e is 1 [ ln(e)=1 ], but did you know that e=2.71828182845905... or that pi, the usual 3.14, is really 3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510 58209 74944 59230 78164 ... and so on ...
Some people have controversies in statistics. When they say average, there are three different ways to do it. Some are interested in (max-min)/2, some are interested in the midway point, and some are actually interested in the true average (add 'em up and divide by n). This might not actaully be controversial, but at least you have read something here that is done in different ways.
| User | Date | K | C | T | P | Comments |
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| Mohd | 11/12/09 | 9 | 10 | 10 | 10 | |
| mikel | 11/11/09 | 10 | 10 | 10 | 10 | The steps were great!! Thank you, I ..... |
| Cindy | 11/10/09 | 10 | 10 | 10 | 10 | Thank you! |
| Dane | 11/05/09 | 9 | 8 | 10 | 10 | |
| Cindy | 11/05/09 | 10 | 10 | 10 | 10 | Thank you, so much! |
It can be said that f²(x) = x^2 + 1, so take the derivative. This gives 2f(x)f'(x) = 2x. Solve for f'(x) and get f'(x) = x/f(x). f"(x) = (f(x) - xf'(x))/f^2(x), and at this point I'll drop the x's
Is that supposed to be f(x) = 2x/(x²+1)? The derivative f'(x) = ((x²+1)2 - 2x*2x)/(x²+1)². That simplifies to f(x) = 2/(x²+1)². The denominator is always positive, so there is 0, so there is no maximum
When x is in radiands, the answer is 1. This is because the Taylor's expansion of sin(x) = x - x^3/3! + x^5/5! - x^7/7! .... Divide by x, and all the terms have an x left in them except for the first
The runner is running at a constant speed of K. The coach is standing at (x,y). The runner is at (a,b). The distance between them is D = √((a-x)² + (b-y)²). The variables area a(t) and b(t).
Note that this can be rewritten. It is really (f(x+h) - f(x)) - (f(x) - f(x-h))/h². It can be further rewritten into ((f(x+h) - f(x))/h - ((f(x) - f(x-h))/h)/h. Using the definition of the derivative

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