Key Points

Exponents And Powers

13 Sections
  • Definition of Negative Exponent

    For any non-zero integer 'a' and a positive integer 'm', a negative exponent indicates the reciprocal of the base raised to the positive exponent. The formula is am=1ama^{-m} = \frac{1}{a^m}.

  • Multiplicative Inverse Property

    A number raised to a negative exponent, ama^{-m}, is the multiplicative inverse of the same number raised to the positive exponent, ama^m. Their product is am×am=amm=a0=1a^m \times a^{-m} = a^{m-m} = a^0 = 1.

  • Zero Exponent Rule

    Any non-zero number raised to the power of zero is always equal to 1. The rule is a0=1a^0 = 1, where a0a \neq 0.

  • Product Rule for Same Base

    When multiplying two exponential terms with the same base, keep the base and add the exponents. The formula is am×an=am+na^m \times a^n = a^{m+n}.

  • Quotient Rule for Same Base

    When dividing two exponential terms with the same base, keep the base and subtract the exponents. The formula is am÷an=amna^m \div a^n = a^{m-n}.

  • Power of a Power Rule

    When raising a power to another power, keep the base and multiply the exponents. The formula is (am)n=amn(a^m)^n = a^{mn}.

  • Power of a Product Rule

    When a product of bases is raised to a power, distribute the exponent to each base. The formula is (a×b)m=am×bm(a \times b)^m = a^m \times b^m.

  • Power of a Quotient Rule

    When a quotient is raised to a power, distribute the exponent to both the numerator and the denominator. The formula is (ab)m=ambm(\frac{a}{b})^m = \frac{a^m}{b^m}, where b0b \neq 0.

  • Negative Exponent of a Fraction

    A fraction raised to a negative exponent is equal to its reciprocal raised to the corresponding positive exponent. The rule is (ab)m=(ba)m(\frac{a}{b})^{-m} = (\frac{b}{a})^m.

  • Standard Form of a Number

    A number is expressed in standard form as k×10nk \times 10^n, where kk is a decimal number such that 1k<101 \leq k < 10, and nn is an integer. This form is used for very large or very small numbers.

  • Standard Form for Small Numbers

    For numbers between 0 and 1, the exponent nn in standard form is negative. For example, the number 0.0000560.000056 can be written as 5.6×1055.6 \times 10^{-5}.

  • Standard Form for Large Numbers

    For numbers greater than or equal to 10, the exponent nn in standard form is positive. For example, the number 942,000,000942,000,000 can be written as 9.42×1089.42 \times 10^8.

  • Converting from Standard Form

    To convert a number from standard form to its usual form, move the decimal point. If the exponent of 10 is positive, move the decimal to the right. If it is negative, move the decimal to the left.

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