You can get an idea by checking the exponential form.

If log<sub>4</sub>(0.287) = 13.9373, then 4<sup>13.9373</sup> = 0.287. **I think not!**

Estimate first. Then you can't make that kind of error.

4<sup>1</sup> = 4

4<sup>0</sup> = 1

4<sup>-1</sup> = ¼ = 0.25

That's it. The answer should be between 0 and -1, probably closer to -1.

The rule you are told to use suggests: log<sub>4</sub>(0.287) = log(0.287)/log(4).

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