(√2)cos15度+(√6)sin15度等于
问题描述:
(√2)cos15度+(√6)sin15度等于
答
(√2)cos15°+(√6)sin15°
=2√2(1/2cos15°+√3/2sin15°)
=2√2(sin30°cos15°+cos30°sin15°)
=2√2sin(30°+15°)
=2