What is a logarithm?
We can explain this by taking a simple power equation such as 23 = 8 and setting each number as an unknown variable. For instance 23 = x is solved by cubing 2, x3 = 8 is solved by taking the cube root of 8, whereas 2x = 8 can't use either of these methods. For this final example we need to introduce the logarithm which is a special function, allowing us to solve the problem. This is defined as loga(b) = c where ac = b and a is called the 'base' of the logarithm which is the number raised by a power (2 in my example). Using this gives log2(2x) = log2(8) as every operation must be applied to both sides of the equation. From before we can see log2(2x) = x therefore leaving us with x = log2(8) which can be solved easily by pressing the correct button on your calculator.
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