Lesson 5-6 Law of Logarithms. Remember: Logs are inverses of exponentials.

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Lesson 5-6 Law of Logarithms

Transcript of Lesson 5-6 Law of Logarithms. Remember: Logs are inverses of exponentials.

Lesson 5-6

Law of Logarithms

Remember:

Remember:Logs are inverses of

exponentials.

Remember:Logs are inverses of

exponentials.

Therefore, all the rules of exponents will also

work for logs.

Laws of Logarithms:

Laws of Logarithms: If M and N are positive real numbers and b is a positive number other than 1,

then:

Laws of Logarithms: If M and N are positive real numbers and b is a positive number other than 1,

then:

Laws of Logarithms: If M and N are positive real numbers and b is a positive number other than 1,

then:

Laws of Logarithms: If M and N are positive real numbers and b is a positive number other than 1,

then:

Laws of Logarithms: If M and N are positive real numbers and b is a positive number other than 1,

then:

Example:

Example: Express logbMN2 in terms of logbM and logbN.

Example: Express logbMN2 in terms of logbM and logbN.

1st: Recognize that you are taking the log of a product (M)(N2)So we can split that up as an addition of two separate logs!

Example: Express logbMN2 in terms of logbM and logbN.

1st: Recognize that you are taking the log of a product (M)(N2)So we can split that up as an addition of two separate logs!

Logb MN2 = logbM + logbN2

Example: Express logbMN2 in terms of logbM and logbN.

1st: Recognize that you are taking the log of a product (M)(N2)So we can split that up as an addition of two separate logs!

Logb MN2 = logbM + logbN2

Now, recognize that we have a power on the number in the 2nd log.

= logbM + 2logbN

Example:

Example:

Example:

Example:

Example:

Example:

Example:

Example:

Example:

Now the domain of all log statements is (0, ∞) x ≠ - 2 so x = 4 is the only solution.

Assignment:

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