化简根号1-sin1+根号（1-cos1）/2
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∵0＜1/2＜π/4
∴0＜sin(1/2)＜cos(1/2)
∴√( 1-sin1 ) + √{ (1-cos1)/2 }
= √{ sin^2(1/2)+cos^2(1/2)-2sin(1/2)cos(1/2) } + √{ (1-[1-2sin^2(1/2)] }
= √{ sin(1/2)-cos(1/2) }^2 + √ sin^2(1/2)
= cos(1/2) - sin(1/2) + sin(1/2)
= cos(1/2)
∴0＜sin(1/2)＜cos(1/2)
∴√( 1-sin1 ) + √{ (1-cos1)/2 }
= √{ sin^2(1/2)+cos^2(1/2)-2sin(1/2)cos(1/2) } + √{ (1-[1-2sin^2(1/2)] }
= √{ sin(1/2)-cos(1/2) }^2 + √ sin^2(1/2)
= cos(1/2) - sin(1/2) + sin(1/2)
= cos(1/2)
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