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Scientific Notation Basics

Sep 6, 2025

Overview

This lecture explains scientific notation, its significance in handling very large or small numbers, methods for calculations, and key rules for operating with scientific notation.

Introduction to Scientific Notation

  • Scientific notation expresses numbers as a digit term times an exponential term (e.g., 5.6 x 10⁻⁹).
  • Useful for simplifying very large or very small numbers.

Structure and Examples

  • Numbers are written as: digit term x 10^exponent.
  • Positive exponents shift the decimal right; negative exponents shift it left.
  • Only digits in the digit term count as significant figures; zeros for place-holding are not significant.

Calculating with Scientific Notation

  • On scientific calculators, input the digit term, press EE/EXP, enter the exponent, and continue normal calculations.
  • Non-scientific calculators require manual exponent calculations.

Rules for Operations

Addition and Subtraction

  • Convert all numbers to the same power of 10, then add or subtract digit terms.
  • Example: (4.215 x 10⁻²) + (3.2 x 10⁻⁴) = 4.247 x 10⁻².

Multiplication

  • Multiply digit terms and add the exponents.
  • Adjust result so one nonzero digit is left of the decimal.
  • Example: (3.4 x 10⁶)(4.2 x 10³) = 1.4 x 10¹⁰.

Division

  • Divide digit terms and subtract exponents.
  • Example: (6.4 x 10⁶)/(8.9 x 10²) = 7.2 x 10³.

Powers and Roots

  • For powers: raise the digit term, multiply exponents.
  • For roots: take root of digit term, divide exponent by the root degree.

Key Terms & Definitions

  • Scientific Notation — A format to write numbers as digit term x 10 to an exponent.
  • Digit Term — The part showing significant figures.
  • Exponential Term — The power of 10 expressing decimal placement.
  • Significant Figures — The digits in a number that carry meaning in terms of accuracy.

Action Items / Next Steps

  • Practice inputting scientific notation on your calculator.
  • Complete the provided quiz questions for mastery.
  • Review exponent manipulation rules for further understanding.