## Math Problem Statement

lim x -> 0 (sin(1/2 * pi + x) - sin(x))/x

## Solution

## Math Problem Analysis

### Mathematical Concepts

Limits

Trigonometry

### Formulas

Sine of a sum identity

L'Hôpital's Rule

### Theorems

L'Hôpital's Rule

### Suitable Grade Level

Advanced High School