- Thu Feb 26, 2015 2:36 pm
- Forum: Discrete Math
- Topic: Find two proofs for the identity
- Replies:
**4** - Views:
**96**

What is "the double counting technique"? Does that refer to "combinatorial" methods? What is "the set" that you're supposed to be "counting"? Are the "two formulas" meant to be the two sides of the identity, so Formula 1 is C(2n, n) and Formula 2 is ...

- Tue Feb 03, 2015 3:43 pm
- Forum: News
- Topic: forum upgrade in progress
- Replies:
**0** - Views:
**165**

The script which runs this forum has been updated by the provider in a manner which has created the need for a partial "clean" install. As a result, the appearance and some features of the forum currently have a changed appearance. The forum appears to be functional. If you encounter any e...

- Fri Jan 16, 2015 12:05 pm
- Forum: Beginning Algebra
- Topic: Domain and Range of a relation
- Replies:
**5** - Views:
**574**

- Fri Jan 16, 2015 12:04 pm
- Forum: Intermediate Algebra
- Topic: reverse formula
- Replies:
**4** - Views:
**420**

The heat emitted from a radiator or heating panel depends primarily on the temperature difference between the radiator and the surrounding air. The heat emission can be expressed as: P = P50 [ (ti - tr) / ln( (ti - ta) / (tr - ta) ) 1 / 49.32 ]n As noted earlier, the expression on the right-hand si...

- Fri Jan 09, 2015 3:27 am
- Forum: Calculus
- Topic: Calculus project
- Replies:
**2** - Views:
**322**

"Real life" projects can quickly become unexpectedly complex. Maybe it would be wise to spend some time looking at projects that **others have posted** online...?

- Sun Jan 04, 2015 5:14 pm
- Forum: Intermediate Algebra
- Topic: Solve this problem, someone who's REALLY good at Algebra 2.
- Replies:
**1** - Views:
**371**

Solve this problem That's kinda your job. But we'll be glad to help you do it. :D Dr. Bones takes a blood sample and finds that it contains 1300 flu viruses per cubic millimeter and is increasing.... After 5 minutes, the virus count is up to 1875. After five more minutes, it is 2400. They have give...

- Fri Jan 02, 2015 5:17 am
- Forum: Trigonometry
- Topic: Missing intermediate results?
- Replies:
**3** - Views:
**323**

This time, *both* of the squared-sine terms became simple sines. I would guess that it's a typo. However, not knowing what comes after, it's hard to say for sure.

- Thu Jan 01, 2015 5:51 pm
- Forum: Trigonometry
- Topic: Missing intermediate results?
- Replies:
**3** - Views:
**323**

- Thu Jan 01, 2015 5:49 pm
- Forum: Trigonometry
- Topic: calculate line and circle problem
- Replies:
**2** - Views:
**350**

- Tue Dec 30, 2014 4:04 pm
- Forum: Trigonometry
- Topic: Navigation: Find my location based on known location
- Replies:
**4** - Views:
**381**

Hmm, not quite, unless I don't understand what you're saying. I don't know where my current location is, but I know how the distance from and bearing to a known location. Are you not trying to find your (currently un-known) location with respect to the known location? It might help if you provided ...