证明:当X≥0时有X*√X-3/2X≥-1/2

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证明:当X≥0时有X*√X-3/2X≥-1/2证明:当X≥0时有X*√X-3/2X≥-1/2证明:当X≥0时有X*√X-3/2X≥-1/2令y=x^(3/2)-3/2*x∴y''=3/2*√x-3/2=

证明:当X≥0时有X*√X-3/2X≥-1/2
证明:当X≥0时有X*√X-3/2X≥-1/2

证明:当X≥0时有X*√X-3/2X≥-1/2
令y=x^(3/2)-3/2*x
∴y'=3/2*√x-3/2=3/2(√x-1),
∴当0≤x<1,时y'<0,为减函数
当x>1时,y'>0,为增函数,
x=1时,y=-1/2
∴函数y=x^(3/2)-3/2*x在[0,+∞)上,最小值为ymin=-1/2,
即X*√X-3/2X≥-1/2