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5-2 Logarithms. What is a logarithm?. Can you find a pattern?. Please graph y = 2 x. By plotting points. Now please graph the inverse. By plotting points. By plotting points. Here it is!. “logarithm” is the term for the inverse of any exponential function.
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5-2 Logarithms What is a logarithm?
Please graph y = 2x By plotting points
Now please graph the inverse By plotting points By plotting points
Here it is! “logarithm” is the term for the inverse of any exponential function. y = 2x The inverse would be x = 2y This is written officially as log2x = y
How to look at logarithms logbx = y can be thought of as logbn = p Then rewrite as n = bp(notice the significance of the variables chosen!!) And then solve it!
Some Rules • n > 0 and p must be real. • b ≠ 1 • If logbx1 =logbx2 then x1 =x2 • Logbb = 1 • logb1 = 0 • logbbx = x 7. blogbx = x
Examples • Log525 2. Log3 • logb16 = 2 4. logb = 5. log6x = -1 6. Find the inverse of log2(2x+4)