sinπ/24-cosπ/24等于多少
问题描述:
sinπ/24-cosπ/24等于多少
答
sinπ/24-cosπ/24=sin15°-cos15°=-【cos15°-sin15°】= -【cos(45°- 30°) - sin(45°- 30°)】=-【 cos45°cos30°+sin45°sin30°- sin45°cos30°+ cos45°sin30°】=-【 √2/2 * cos30°+√2/2 * sin30...