【简答题】若 有意义,则 = , 若 , 则± =
【单选题】I’d like to do something for you_____ everything you have done for me.
【单选题】--Do you think you will give me a hand in time of trouble? --I’d like to do something for you ______ everything you’ve done for me.
【单选题】I’d like to do something for you ____ everything you’ve done for me.
【简答题】对于实数 ,有下列命题: ①若 ,则 ; ②若 ,则 ; ③若 ,则 ; ④若 ,则 ; ⑤若 , ,则 . 其中真命题是____(填序号).
【简答题】---Would you like to play basketball with us ? ---- I’d like to do .
【简答题】设 ,现有下列命题:①若 ,则 ;②若 ,则 ; ③若 ,则 ;④若 ,则 其中正确命题的序号为 .
【简答题】定义“正对数”: ,现有四个命题: ①若 ,则 ; ②若 ,则 ; ③若 ,则 ④若 ,则