已知函数f(x)=5sin(x+π/3)+2cos^2(x+π/3)

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    f(x)=5sin(x+π/3)+2cos平方(x+π/3)

    =5sin(x+π/3)+[2cos平方(x+π/3)+2sin平方(x+π/3)]-2sin平方(x+π/3)

    =5sin(x+π/3)+2-2sin平方(x+π/3)

    设sin(x+π/3)=t

    f(x)=-2t平方+5t+2

    =-2(t-5/4)平方+41/8 t∈[-1,1]

    1、所以fmax=-2(1-5/4)平方+41/8=5

    此时t=1 所以sin(x+π/3)=1

    x取值集合:{x|x=2kπ+π/6(k∈Z)}

    2、若定义域为[-π/2,π/2]

    则t∈[-1/2,1/2]

    fmax=-2(1/2-5/4)平方+41/8=4

    fmin=-2(-1/2-5/4)平方+41/8=-1

    函数的值域[4,-1]

    祝你考试一路顺风~~~~~~