\[
\boxed{\text{The equation is true for all } x.}
\]
The first statement is:
\[
\frac{2x-1}{x^{2}+4}=\frac{2x-1}{x^{2}}+\frac{2x-1}{4}
\]
To verify, we need to find a common denominator for the right side:
\[
\frac{2x-1}{x^{2}}+\frac{2x-1}{4} = \frac{(2x-1) \cdot 4 + (2x-1) \cdot x^2}{x^2 \cdot 4}
\]
Simplifying the numerator:
\[
4(2x-1) + x^2(2x-1) = 8x - 4 + 2x^3 - x^2
\]
The expression does not simplify to \((2x-1)\), so the statement is false.
The second statement is:
\[
\frac{2x-1}{x^{2}+4}=\frac{2x}{x^{2}+4}-\frac{1}{x^{2}+4}
\]
Combine the right side:
\[
\frac{2x}{x^{2}+4} - \frac{1}{x^{2}+4} = \frac{2x - 1}{x^{2}+4}
\]
This is equivalent to the left side, so the statement is true.
- First statement: False
- Second statement: True
\[
\boxed{\text{Second statement is true.}}
\]
The tangent function is negative in the second and fourth quadrants. The reference angle for \(\tan(\theta) = \sqrt{3}\) is \(\frac{\pi}{3}\).
Thus, the angles in \([0, 2\pi]\) where \(\tan(\theta) = -\sqrt{3}\) are:
- In the second quadrant: \(\pi - \frac{\pi}{3} = \frac{2\pi}{3}\)
- In the fourth quadrant: \(2\pi - \frac{\pi}{3} = \frac{5\pi}{3}\)
\[
\boxed{\theta = \frac{2\pi}{3}, \frac{5\pi}{3}}
\]