Integral Sine Double Angle
1. **State the problem:** Evaluate the definite integral $$\int_0^{\frac{\pi}{2}} \sin(2x) \, dx$$.
2. **Recall the formula:** The integral of $$\sin(ax)$$ with respect to $$x$$ is $$-\frac{1}{a} \cos(ax) + C$$, where $$a$$ is a constant.
3. **Apply the formula:** Here, $$a = 2$$, so
$$\int \sin(2x) \, dx = -\frac{1}{2} \cos(2x) + C$$.
4. **Evaluate the definite integral:**
$$\int_0^{\frac{\pi}{2}} \sin(2x) \, dx = \left[-\frac{1}{2} \cos(2x)\right]_0^{\frac{\pi}{2}} = -\frac{1}{2} \cos(\pi) + \frac{1}{2} \cos(0)$$.
5. **Calculate the cosine values:**
$$\cos(\pi) = -1$$ and $$\cos(0) = 1$$.
6. **Substitute and simplify:**
$$-\frac{1}{2} (-1) + \frac{1}{2} (1) = \frac{1}{2} + \frac{1}{2} = 1$$.
**Final answer:**
$$\int_0^{\frac{\pi}{2}} \sin(2x) \, dx = 1$$.