Math Formulas

tags : Math

Meta §

• NSOD: Not sure of the derivation

Basic §

Multiplication §

• To do 17x15 in head, do (15+2)x15 = 15x15 + 15x2 = 255 (becomes easier)

Logarithm §

• See Logarithm
• Exponent of a +ve number with irrational exp
  • NSOD
  • $a^b=exp(b\ln (a))=e^{\ln a^b}=e^{b\ln a}$
  • This apparently works for other bases like 10 also instead of \e.

Series §

Gauss formula §

• Gauss formula to add number of sequence for arbitrary range