22.已知函數(shù)y=f(x)是指數(shù)函數(shù),且該函數(shù)的圖象經(jīng)過點(diǎn)(2,9),設(shè)函數(shù)
是定義在R上的奇函數(shù).
(Ⅰ)求函數(shù)f(x)、g(x)的解析式;
(Ⅱ)利用函數(shù)單調(diào)性定義證明函數(shù)y=g(x)的單調(diào)性;
(Ⅲ)若對(duì)任意m∈[1,4],不等式g(m
2+2m+t)-g(2m
2-2m+3)>0恒成立,求實(shí)數(shù)t的取值范圍.