求sinx+cosx>1的x的集合

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求sinx+cosx>1的x的集合求sinx+cosx>1的x的集合求sinx+cosx>1的x的集合sinx+cosx>1√2sin(x+π/4)>1sin(x+π/4)>√2/2则:2kπ+π/4

求sinx+cosx>1的x的集合
求sinx+cosx>1的x的集合

求sinx+cosx>1的x的集合
sinx+cosx>1
√2sin(x+π/4)>1
sin(x+π/4)>√2/2
则:
2kπ+π/4≤x+π/4≤2kπ+3π/4
2kπ≤x≤2kπ+π/2,其中,k∈Z

sinx+cosx=√2sin(x+π/4)>1
sin(x+π/4)>√2/2
2kπ+π/4所以是{x|x=2kπ

√2sin(x+π/4)>1
sin(x+π/4)>1/√2
2kπ+π/4解出x,写成x的集合,为所求