若函数f(x)=a^2sin2x+(a-2)cos - 知识问答

若函数f(x)=a^2sin2x+(a-2)cos2x的图象

1个回答

f(x)在x=-π/8时,取最大值或最小值
即f(-π/8)=±√[a^4+(a-2)^2]
√2/2[-a^2+(a-2)]=±√[a^4+(a-2)^2]
1/2[-a^2+(a-2)]^2 = a^4+(a-2)^2
a^2+a-2=0
a=1或a=-2

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