My Favorite Food
I like different kinds of food. But my favorite food is mooncakes. I like them very much. They are very delicious and popular.
Mooncakes are delicious round cakes. Some have eggs or nut
乘车人不得携带____等危险物品,不得向车外抛撒物品。
剧场能坐870人.一张票8元,如果一场票都卖完了,这场的票房收入是多少元?
____×____=____(元)
用下列词语造句
①感染
②商量
已知在Rt△ABC中,∠C=90°,它的三边长分别为a,b,c,对于同一个锐角A的正弦,余弦存在关系式sin2A+cos2A=1试说明.
解:∵sinA= ,cosA= .
∴sin2A+cos2A= ,
∵a2+b2=c2,∴sin2A+cos2A=1.