Question

1.指出下列函数的单调区间及单调性:

Answer 1

(1)

f(x)=(x+3)/(x-1)

=(x-1+4)/(x-1)

=1+4/(x-1)

因为4/(x-1)

在(1,+∞)和(-∞,1)上单调递减

所以f(x)在(1,+∞)和(-∞,1)上单调递减

(2)

y=|-x^2+2x+3|

当-x^2+2x+3>=0

x^2-2x-3