We are given the functional equation:
\[ f(x) + 2f\left(\frac{1}{x}\right) = 3x \]
We are asked to find the sum of all possible values of $x$ for which $f(x) = 3$.
Substitute $f(x) = 3$ into the equation:
\[ 3 + 2f\left(\frac{1}{x}\right) = 3x \]
Solve for $f\left(\frac{1}{x}\right)$:
\[ 2f\left(\frac{1}{x}\right) = 3x - 3 \]
\[ f\left(\frac{1}{x}\right) = \frac{3x - 3}{2} \]
Now, substitute $x = \frac{1}{x}$ into the original equation:
\[ f\left(\frac{1}{x}\right) + 2f(x) = \frac{3}{x} \]
This results in a system of equations, which can be solved to find the value of $x$. After solving the system, we find that the sum of all possible values of $x$ for which $f(x) = 3$ is -3.
If the domain of the function \[ f(x)=\log\left(10x^2-17x+7\right)\left(18x^2-11x+1\right) \] is $(-\infty,a)\cup(b,c)\cup(d,\infty)-\{e\}$, then $90(a+b+c+d+e)$ equals
For any natural number $k$, let $a_k = 3^k$. The smallest natural number $m$ for which \[ (a_1)^1 \times (a_2)^2 \times \dots \times (a_{20})^{20} \;<\; a_{21} \times a_{22} \times \dots \times a_{20+m} \] is: