作业帮已知f(x)=sin²x+2sinxcosx+3cos²x,x∈R,求:函数f(x)在区间[0,π/2]上的单调增区间
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![已知f(x)=sin²x+2sinxcosx+3cos²x,x∈R,求:函数f(x)在区间[0,π/2]上的单调增区间](/uploads/image/z/572286-30-6.jpg?t=%E5%B7%B2%E7%9F%A5f%28x%29%3Dsin%26%23178%3Bx%2B2sinxcosx%2B3cos%26%23178%3Bx%2Cx%E2%88%88R%2C%E6%B1%82%3A%E5%87%BD%E6%95%B0f%28x%29%E5%9C%A8%E5%8C%BA%E9%97%B4%5B0%2C%CF%80%2F2%5D%E4%B8%8A%E7%9A%84%E5%8D%95%E8%B0%83%E5%A2%9E%E5%8C%BA%E9%97%B4)
已知f(x)=sin²x+2sinxcosx+3cos²x,x∈R,求:函数f(x)在区间[0,π/2]上的单调增区间
已知f(x)=sin²x+2sinxcosx+3cos²x,x∈R,求:函数f(x)在区间[0,π/2]上的单调增区间
已知f(x)=sin²x+2sinxcosx+3cos²x,x∈R,求:函数f(x)在区间[0,π/2]上的单调增区间
f(x)=1+sin2x+2cos^2x
=1+sin2x+1+cos2x
=√2sin(2x+π/4)+2
2kπ-π/2≤2x+π/4≤2kπ+π/2
kπ-3π/8≤x≤kπ+π/8
[0,π/8]