——_________ is he going to be after he leaves school?
——He's going to be a doctor.
A:Who
B:What
C:Which
D:Why
已知a+b3=b+c4=c+a5,求a-b-cc-a+b的值.
半径2厘米的圆的周长和面积是相等的.
在△ABC中,角A,B,C所对的边分别为a,b,c,若3acosB+bcosA=2csinC,a+b=4,且△ABC的面积的最大值为3,则此时△ABC的形状为( )
①16×14=224
②23×27=621
③32×38=1216…