Sec Tan Sum
1. **Problem Statement:** Given that $\sec \theta = a + \frac{1}{4a}$, find the value of $\sec \theta + \tan \theta$.
2. **Recall the identity:**
$$\sec^2 \theta - \tan^2 \theta = 1$$
This implies:
$$\tan^2 \theta = \sec^2 \theta - 1$$
3. **Calculate $\sec^2 \theta$:**
$$\sec \theta = a + \frac{1}{4a}$$
Square both sides:
$$\sec^2 \theta = \left(a + \frac{1}{4a}\right)^2 = a^2 + 2 \cdot a \cdot \frac{1}{4a} + \left(\frac{1}{4a}\right)^2 = a^2 + \frac{1}{2} + \frac{1}{16a^2}$$
4. **Calculate $\tan^2 \theta$:**
$$\tan^2 \theta = \sec^2 \theta - 1 = \left(a^2 + \frac{1}{2} + \frac{1}{16a^2}\right) - 1 = a^2 - \frac{1}{2} + \frac{1}{16a^2}$$
5. **Calculate $\tan \theta$:**
Since $\tan \theta$ can be positive or negative, but we assume positive for this problem,
$$\tan \theta = \sqrt{a^2 - \frac{1}{2} + \frac{1}{16a^2}}$$
6. **Calculate $\sec \theta + \tan \theta$:**
We want to simplify:
$$a + \frac{1}{4a} + \sqrt{a^2 - \frac{1}{2} + \frac{1}{16a^2}}$$
7. **Simplify the expression under the square root:**
Rewrite the radicand as:
$$a^2 - \frac{1}{2} + \frac{1}{16a^2} = \left(a - \frac{1}{4a}\right)^2$$
Because:
$$\left(a - \frac{1}{4a}\right)^2 = a^2 - 2 \cdot a \cdot \frac{1}{4a} + \left(\frac{1}{4a}\right)^2 = a^2 - \frac{1}{2} + \frac{1}{16a^2}$$
8. **Therefore:**
$$\tan \theta = \left|a - \frac{1}{4a}\right|$$
Assuming $a > 0$, we take positive value:
$$\tan \theta = a - \frac{1}{4a}$$
9. **Sum $\sec \theta + \tan \theta$:**
$$\left(a + \frac{1}{4a}\right) + \left(a - \frac{1}{4a}\right) = a + \frac{1}{4a} + a - \frac{1}{4a} = 2a$$
**Final answer:**
$$\boxed{2a}$$