A. Why are you sad?
B. Because I got a kitten.
C. Because I did my homework very slowly.
计算(− 34+ 112− 58+ 56)×(−24)时,可以使运算简便的是运用( )
已知sinα-π4=13,则cosπ4+α的值等于( )
一辆汽车用3.22千克汽油能行驶23千米,照这样计算,