# Quaternion::Inverse

```cpp
Quaternion Inverse() const;
```

求四元数的逆。如果四元数已归一化，逆等于共轭。

**返回：** 四元数的逆

**线程安全：** ✅

**复杂度：** O(1)

**示例：**

```cpp
#include <XCEngine/Math/Quaternion.h>

using namespace XCEngine::Math;

Quaternion q = Quaternion::FromAxisAngle(Vector3::Up(), Math::Radians(90.0f));
Quaternion inv = q.Inverse();

Quaternion identity = q * inv;
```

## 相关文档

- [Quaternion](quaternion.md) - 返回类总览
- [Normalized](normalized.md) - 归一化四元数