Question

How do you change `2^0.4 = 1.320` into log form?

Answer 1

`2^0.4 = 1.320 hArr log_2 1.320 = 0.4`

Explanation:

log form and index form give the same information and are interchangeable.

`log_a b = c hArr a^c = b`

"The base stays the base and the other two swop around"

`2^0.4 = 1.320 hArr log_2 1.320 = 0.4`

In index form: `2^1 = 2, " so " 2^0.4` will be less than 2.
The value 1.320 seems reasonable.

In log form, the question is, "What power or index of 2 will give 0.4?"