We need to solve the inequality $\sqrt{(a-3)^2} \sin a - 3 < 0$.
2025/3/11
1. Problem Description
We need to solve the inequality .
2. Solution Steps
First, we simplify the square root:
.
So the inequality becomes , which can be rewritten as .
Now, we consider two cases:
Case 1: . In this case, , so the inequality becomes .
Case 2: . In this case, , so the inequality becomes .
Now, let us consider the expression . Since , then
.
So, if , then .
We have , which implies .
Adding 3 to all parts of the inequality, we have .
If , then , so . Thus is a solution.
If , then , and , so . Thus is a solution.
If , then . , so . Thus is a solution.
If , then . Also, we know that , so could be less than
3. If $a$ is close to $2\pi$, say $a = 2\pi \approx 6.28$, then $|a-3| = |6.28-3| = 3.28$. $\sin a = \sin 2\pi = 0$, so $|a-3|\sin a = 0 < 3$. However, as $a$ gets larger, it is difficult to determine whether the inequality holds in general.
Let's analyze when and are not satisfied. This occurs when and or when and .
When , we are guaranteed that the inequalities hold.
When , the inequalities are satisfied for any .
Consider the original inequality .
This inequality is satisfied when or when when .