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函数y=2sin(x+π/12)+√2cos(x+π/3)求最大值 过程详细点

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函数y=2sin(x+π/12)+√2cos(x+π/3)求最大值 过程详细点
y=2sin(x+π/12)+√2cos(x+π/3)
=2sin(x+π/12)+ √2cos((x+π/12)+π/4)
=2sin(x+π/12)+ √2cos(x+π/12)*cosπ/4-√2sin(x+π/12)*sinπ/4
=2sin(x+π/12)+ cos(x+π/12)-sin(x+π/12)
=sin(x+π/12)+ cos(x+π/12)
=√2sin(x+π/12+π/4)
=√2sin(x+π/3)
当x+π/3=π/2+2kπ(k=0,1,2.) 时取最大值
即x=π/6+2kπ(k=0,1,2.) 时取最大值,且最大值为√2