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已知函数F(x)=sin(2x+π6),x∈R.(1)求函数F...

(1)T=2π2=π.(2)由2kπ-π2≤2x+π6≤2kπ+π2,得kπ-π3≤x≤kπ+π6,k∈Z,∴函数的单调增区间为[kπ-π3,kπ+π6](k∈Z).(3)∵x∈[0,π2],∴2x+π6∈[π6,7π6],∴-12≤sin(2x+π6)≤1,∴当2x+π6=π2,即x=π6时函数有最大值1,当2x+π6=7π6时,即x=π2,函数有...

f(x)=cosxsin(x+π/6)-cos2x-1/4, =cosx(√3/2sinx+1/2cosx)-cos2x-1/4, =√3/2sinxcosx+1/2(cosx)^2-cos2x-1/4, =√3/4sin2x+1/4(1+cos2x)-cos2x-1/4, =√3/4sin2x-3/4cos2x =√3/2(1/2sin2x-√3/2cos2x) =√3/2sin(2x-π/3) 2x-π/3∈[2kπ-π/2,2kπ+π/2]单...

见图 解:(I)f(x)==sin2x+cos2x=sin(2x+). 令 2kπ-≤(2x+)≤2kπ+,可得 kπ-≤x≤kπ+,k∈z. 即f(x)的单调递增区间为[kπ-,kπ+],k∈z. (II)在△ABC中,由,可得sin(2A+)=,∵<2A+<2π+, ∴<2A+= 或,∴A= (或A=0 舍去). ∵b,a,c成...

解: f(x)=sin2xcosπ/6+cos2xsinπ/6+sin2xcosπ/6-cos2xsinπ/6+1+cos2x =2sin2xcosπ/6+cos2x+1 =√3sin2x+cos2x+1 =2sin(2x+π/6)+1 ⑴f(x)取得最大值3,此时2x+π/6=π/2+2kπ,即x=π/6+kπ,k∈Z 故x的取值集合为{x|x=π/6+kπ,k∈Z} ⑵由2x+π/6∈[-π/2+2kπ...

(1) 2x+π6 0 π2 π 3π2 2π x ?π12 π6 5π12 2π3 11π12 y=2sin(2x+π6) 0 2 0 -2 0…(2分)…(5分)(2)f(x)的最大值为2;…(7分)此时自变量x取值的集合为{x|x=kπ+π6,k∈Z}…(10分)(3)函数的对称轴方程为 x=kπ2+π6,k∈z…(14分)

(I)∵函数f(x)=sin(7π6?2x)+2cos2x?1=sin7π6cos2x-cos7π6sin2x+cos2x=32sin2x+12cos2x=sin(2x+π6).故函数f(x)的周期为T=2π2=π.再令 2kπ-π2≤2x+π6≤2kπ+π2,k∈z,求得 kπ-π3≤x≤kπ+π6,k∈z,故单调递增区间为[kπ-π3,kπ+π6],k∈z.(II)...

f(x)=sin(2x+π/6)+1 1、T=2π/2=π -1=

(1) f(x)=sin(2(x-π/12)) x∈[0,π]时,2(x-π/12)∈[-π/6,11π/6] 单调递减区间是2(x-π/12)∈[π/2,3π/2] 即x-π/12∈[π/4,3π/4] 则x∈[π/3,5π/6] (2)x∈[-π/12,π/2]时, 2(x-π/12)∈[-π/3,5π/6] 而当2(x-π/12)∈[-π/3,π/3]时,sin(2(x-π/12))∈[sin(-π/3),...

(1)函数f(x)=sin(2x-π6)的最小正周期为T=π.(2)∵x∈(π6,2π3)上,∴2x-π6∈(π6,7π6).由于关于x的方程f(x)=2t在(π6,2π3)上有且只有一个根,故函数y=f(x)的图象和直线y=2t只有一个交点,∴2t=1或?12<2t≤12,解得 t=12或?14<t≤14....

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