題2:http://i177.photobucket.com/albums/w235/comicspartys/book/1.jpg
題4:http://i177.photobucket.com/albums/w235/comicspartys/book/2.jpg
題7:http://i177.photobucket.com/albums/w235/comicspartys/book/3-2.jpg
題10:http://i177.photobucket.com/albums/w235/comicspartys/book/4-3.jpg
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求:2b,4,10a,c(淨要答案)
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感謝各位幫忙
更新1:
先感謝熱心的解答 ================ 但我想問問題4a中 點解個u係 -6,而唔係any real number?仲有個 入 點解唔係 -9? ================ 我的運算如下: http://i177.photobucket.com/albums/w235/comicspartys/book/6.jpg
