Question

求下列函数的单调区间(1)y=sin(x+π/4) (2)y=3cosx+1

Answer 1

1 2kπ-π/2<=x+π/4<=2kπ+π/2 得函数的增区间为2kπ-3π/4<=x<=2kπ+π/4
2kπ+π/2<=x+π4<=2kπ+3π/2 的函数的减区间为2kπ+π/4<=x<=2kπ+5π/4
2 增区间为2kπ-π<=x<=2kπ
减区间为2kπ<=x<=2kπ+π