(Ⅰ)由题意得 ························· 2分 因为cosA≠0, ···························· 3分 所以tanA="1." ····························· 4分 (Ⅱ)由(Ⅰ)知tanA=1得 ······················· 5分 =························ 6分 =····················· 7分 因为xR,所以.······················ 8分 当时,f(x)有最大值,··················· 10分 当sinx=-1时,f(x)有最小值-2,··················· 11分 所以所求函数f(x)的值域是·················· 13分 |