【用戶】meimei
【年級】高三下
【評論內容】sin20°cos70° + sinl0°sin50=1/2[sin(20°+70°)+sin(20°-70°)]-1/2[cos(10°+50°)-cos(10°-50°)]
【用戶】meimei
【年級】高三下
【評論內容】sin20°cos70° + sinl0°sin50=1/2[sin(20°+70°)+sin(20°-70°)]-1/2[cos(10°+50°)-cos(10°-50°)]
【用戶】meimei
【年級】高三下
【評論內容】sin20°cos70° + sinl0°sin50=1/2[sin(20°+70°)+sin(20°-70°)]-1/2[cos(10°+50°)-cos(10°-50°)]