Question

求函数y=√(x-1)+1(x≥1)的反函数

Answer 1

y=√(x-1)+1(x≥1)

所以 y>=1

y-1=√(x-1)(x≥1,y>=1)

x - 1 = (y-1)^2 = y^2 - 2y + 1

x = y^2 - 2y + 2

反函数是 y' = x^2 - 2x + 2 (x≥1)