# The Exponential Notation for the Floating Real Numbers

Our scientific calculators deal sometimes with numbers with a $$E$$ inside: this is the so called Exponential, or Scientific Notation.

But what does that mean, and how to read such numbers?

# Music and Math: how is the Major C scale built?

The Greeks discovered the link between the musical intervals and the length of a string. The simpler example is that half the string sounds at the octave of the whole string. We know now that this corresponds to twice the frequency of the vibration.