.
You are given
= , = , = . (1)
They want you find .
Solution
From (1), you have, using the change of base formula
= ; = and = .
Transform the last equation
= = + + = + + .
It implies
= - - = = = .
Hence, = = = 60.
ANSWER. = 60.
Solved.
T h a t ' s a l l.
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| It is how this problem SHOULD BE SOLVED. |
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For your safety, IGNORE everything that @MathLover1 wrote in her post.
This woman demonstrates extreme activity, but solves many problems INCORRECTLY, or in a way,
which is not adequate and/or is not effective.
Unfortunately.
So, be careful, considering her contribution (!)