Do you know the perfect number?
A perfect number can be expressed by the sum of its positive divisors except itself. For example, the specified divisors […]
You need to know the following math before taking introductory physics.
I have seen the following mathematical errors for years in physics classes. \(\sqrt{16ab} = 4ab \) The correct one should […]
Can you find the errors in these equations?
Can you correct the following equations? \((a+b)^2 = a^2 + b^2 \) \(\frac{1}{a+b} = \frac{1}{a} + \frac{1}{b} \) \(\frac{10^{10}}{2} = […]
If a major league pitcher throws a ball against gravity, …
Suppose the pitcher can always throw a ball at 100 mi/h. If he throws vertically upward with that speed against […]
Can you solve this problem? (The area of squares)
In the picture, there are three squares. Each size of square is different, and the they are aligned as shown. […]
Do you know Pell’s equation?
An indeterminate equation is an equation that has more than one solutions. Pell’s equation is one of them that is […]
Need physics help?
Hi there! Are you taking introductory physics courses? Are you doing well in the class? Do you need any help […]