Multiple choice

The sum of the roots of the equation x + 1 - 2log2(3 + 2x) + 2log4(10 - 2-x) = 0 is:

  1. log212

  2. log214

  3. log211

  4. log213
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Simplify the equation using log properties. x + 1 - log2((3+2^x)^2) + log2(10-2^-x) = 0. x + 1 + log2((10-2^-x)/(3+2^x)^2) = 0. Solving this leads to x=1 and x=log2(something). The sum of roots is log2(11).

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