Pearson Algebra 2 Common Core, 2011
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Pearson Algebra 2 Common Core, 2011 View details
4. Rational Expressions
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Exercise 58 Page 533

Set up an equation and apply the definition of a logarithm.

-5

Practice makes perfect
To evaluate the given logarithm, we will start by writing a logarithmic equation. log_2 1/32=x In order to solve this equation, we can rewrite it as an exponential equation by using the definition of a logarithm. log_b x= y ⇔ x= b^y The above means that the logarithm y is the exponent to which b must be raised to get x. For our exercise, x is the exponent to which 2 must be raised to get 132. log_2 1/32= x ⇔ 1/32= 2^x Finally, to solve the exponential equation, we will rewrite the terms so that they have a common base.
1/32 = 2^x
1/2^5 = 2^x
2^(-5) = 2^x
Now we have two equivalent expressions with the same base. If both sides of the equation are equal, the exponents must also be equal.
2^(-5) = 2^x
-5 = x
x = -5