问题
填空题
函数y=2-x+1-3(x>1)的反函数为______.
答案
∵函数y=2-x+1-3(x>1)
∴y+3=2-x+1,
∴-x+1=log2(y+3),
∴x=1-log2(y+3)(-3<y<2)
故函数y=2-x+1-3(x>1)的反函数为y=1-log2(x+3)(-3<x<2)
故答案为:y=1-log2(x+3)(-3<x<2)
函数y=2-x+1-3(x>1)的反函数为______.
∵函数y=2-x+1-3(x>1)
∴y+3=2-x+1,
∴-x+1=log2(y+3),
∴x=1-log2(y+3)(-3<y<2)
故函数y=2-x+1-3(x>1)的反函数为y=1-log2(x+3)(-3<x<2)
故答案为:y=1-log2(x+3)(-3<x<2)