求函数y=sin方x+sinxcos(派/6-x)的周期和单调递增区间,
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求函数y=sin方x+sinxcos(派/6-x)的周期和单调递增区间,
求函数y=sin方x+sinxcos(派/6-x)的周期和单调递增区间,
求函数y=sin方x+sinxcos(派/6-x)的周期和单调递增区间,
y=sin方x+sinxcos(派/6-x)
=(3/2)sin²x+(√3/2)sinxcosx
=(√3/2)sin(2x-π/3)+3/4
周期为 π
增区间为[kπ-π/12,kπ+5π/12] k∈Z
函数y=sin方x+sinxcos(派/6-x)
=sinx(sinx+cosπ/6cosx+sinπ/6sinx)
=sinx(√3/2cosx+3/2sinx)
=√3/4sin2x+3/2sin^2x
=√3/4sin2x+3/2(1-coss2x)/2
=√3/4sin2x-3/4coss2x+3/4
=√3/2(1/2sin2x-√3/2c...
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函数y=sin方x+sinxcos(派/6-x)
=sinx(sinx+cosπ/6cosx+sinπ/6sinx)
=sinx(√3/2cosx+3/2sinx)
=√3/4sin2x+3/2sin^2x
=√3/4sin2x+3/2(1-coss2x)/2
=√3/4sin2x-3/4coss2x+3/4
=√3/2(1/2sin2x-√3/2cos2x)+3/4
=√3/2sin(2x-π/3)+3/4
周期T=2π/2=π
单调递增区间 2kπ-π/2<=2x-π/3<=2kv+π/2
得 增区间 [kπ-π/12,kπ+5π/12] k∈Z
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y=sin方x+sinxcos(派/6-x)
=sin²x+sinx[√3/2cosx+1/2sinx]
=(3/2)sin²x+(√3/2)sinxcosx
=(3/4)(1-cos2x)+(√3/4)sin2x
=(√3/4)sin2x-(3/4)cos2x+3/4
=(√3/2)sin(2x-π/3)+3/4<...
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y=sin方x+sinxcos(派/6-x)
=sin²x+sinx[√3/2cosx+1/2sinx]
=(3/2)sin²x+(√3/2)sinxcosx
=(3/4)(1-cos2x)+(√3/4)sin2x
=(√3/4)sin2x-(3/4)cos2x+3/4
=(√3/2)sin(2x-π/3)+3/4
周期为 2π/2=π
单调增区间为 2x-π/3∈[2kπ-π/2,2kπ+π/2]
x∈[kπ-π/12,kπ+5π/12]
所以掉增区间为 [kπ-π/12,kπ+5π/12] k∈Z
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