函数f(x)=sin(wx+φ)(w>0,0≦φ≦π)是R上的偶函数,最小正周期π
w=2,φ=π/2
f(x)=-cos2x
g(x)=f(x)+f(x+π/4)=-cos2x-cos2(x+π/4)=sin2x-cos2x=√2sin(2x-π/4)
单调递增区间为[kπ-π/8,kπ+3π/8] (k为整数)
函数f(x)=sin(wx+φ)(w>0,0≦φ≦π)是R上的偶函数,最小正周期π
w=2,φ=π/2
f(x)=-cos2x
g(x)=f(x)+f(x+π/4)=-cos2x-cos2(x+π/4)=sin2x-cos2x=√2sin(2x-π/4)
单调递增区间为[kπ-π/8,kπ+3π/8] (k为整数)