Monday, September 20, 2010

what i learned last week

what i learned last week was how to solve the nth root with irrational numbers and how to solve for absolute error (ex)
One commonly distinguishes between the relative error and the absolute error. The absolute error is the magnitude of the difference between the exact value and the approximation. The relative error is the absolute error divided by the magnitude of the exact value. The percent error is the relative error expressed in terms of per 100.
As an example, if the exact value is 50 and the approximation is 49.9, then the absolute error is 0.1 and the relative error is 0.1/50 = 0.002. The relative error is often used to compare approximations of numbers of widely differing size; for example, approximating the number 1,000 with an absolute error of 3 is, in most applications, much worse than approximating the number 1,000,000 with an absolute error of 3; in the first case the relative error is .003 and in the second it is only .000003

2 comments:

  1. Nice summary
    Remember to multiply by 100 to get relative error into a percent
    Keep up the good work summarizing

    ReplyDelete
  2. you are missing a summary of interior angles of polygons
    2

    ReplyDelete