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www.001rz.com已知函数f(x)=cos²x,g(x)=1+1/2sin2x
日期：2021-06-23 05:11:28 人气：64
(1)
f(x)=cos²x
g(x)=1+(1/2)sin2x
f(x)=g(x)
(cosx)^2 =1+(1/2)sin2x
(cos2x +1)/2 = 1+(1/2)sin2x
sin2x- cos2x + 1 =0
√2sin(2x-π/4) =-1
2x-π/4 = -π/4
x = 0
ie a=0
(2
f(x)=cos²x
g(x)=1+(1/2)sin2x
f(x)=g(x)
(cosx)^2 =1+(1/2)sin2x
(cos2x +1)/2 = 1+(1/2)sin2x
sin2x- cos2x + 1 =0
√2sin(2x-π/4) =-1
2x-π/4 = -π/4
x = 0
ie a=0
(2