Can you explain what a logarithm is?

We can think of taking the logarithm base a of a number b (logab) as "the number of times we need to multiply a by itself to get b". So for example, log2 16 = 4, since we need to multiply 2 by itself 4 times to get 16 (2 x 2 x 2 x 2 = 16, or 24 = 16).In more detail, logarithms are the inverse operations to exponentiation. This means that if you are given a number x and told to raise y to the power of x to get z, then logy z = x. i.e. if we have the operation "raise y to the power of ___", then performing the operation "take the logarithm base y" gives us back our original input ____. So if yx = z, then performing the inverse operation to both sides gives us back x: logy yx = logy z ==> x = logy z

DH
Answered by Daniel H. Maths tutor

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