作业帮如图,计算题,这个题
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如图,计算题,这个题
如图,计算题,
这个题
如图,计算题,这个题
原式=(a³-6a²+4a+8-a³+3a²-2a)/a(a-2)(a²-4a-4)*(a-2)/(a-4)
=(-3a²+2a+8)/a(a-2)(a²-4a-4)*(a-2)/(a-4)
=-(3a+4)(a-2)/a(a-2)(a²-4a-4)*(a-2)/(a-4)
=-(3a+4)(a-2)/a(a²-4a-4)(a-4)
当a=√2-1时,
原式=-（3√2+1)(√2-3)/(√2-1)(3-2√2-4√2+4-4)(√2-5)
=-(3-8√2)/(7-6√2)((3-6√2)
=-(3-8√2)/(93-60√2)
=-(3-8√2)(93+60√2)/(93²-60²×2)
=(681+564√2)/1449
图片没上来
[(a-2)/(a^2-2a)-(a-1)/(a^2-4a+4)]÷[(a-4)/(a-2)]
=(a-2)^2/a(a-2)(a-4)-(a-1)(a-2)/(a^2-4a-4)(a-4)
=(a-2)/a(a-4)-(a-1)(a-2)/(a^2-4a-4)(a-4)
=(√2-1-2)/(√2-1)(√2-1-4)-(√2-1-1)(√2-1-2)/[(√2...
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[(a-2)/(a^2-2a)-(a-1)/(a^2-4a+4)]÷[(a-4)/(a-2)]
=(a-2)^2/a(a-2)(a-4)-(a-1)(a-2)/(a^2-4a-4)(a-4)
=(a-2)/a(a-4)-(a-1)(a-2)/(a^2-4a-4)(a-4)
=(√2-1-2)/(√2-1)(√2-1-4)-(√2-1-1)(√2-1-2)/[(√2-1)^2-4(√2-1)-4](√2-1-4)
=(√2-3)/(√2-1)(√2-5)-(√2-2)(√2-3)/[2-2√2+1]-4√2+4-4](√2-5)
=(√2-3)/(√2-1)(√2-5)-(√2-2)(√2-3)/[3-6√2](√2-5)
=(√2-3)/(2-6√2+5)-(2-5√2+6)/(33√2-27)
=(√2-3)/(7-6√2)-(8-5√2)/(33√2-27)
=(√2-3)(33√2-27)/(7-6√2)(33√2-27)-(8-5√2)(7-6√2)/(33√2-27)(7-6√2)
=[(√2-3)(33√2-27)-(8-5√2)(7-6√2)]/(33√2-27)(7-6√2)
=[(147-126√2)-(56-83√2+60)]/(393√2-585)
=(31-43√2)/(393√2-585)
=(31-43√2)/3(131√2-195)
=(31-43√2)(131√2-195)/3(131√2-195)(131√2+195)
=（12446√2-17311）/11109
=12446√2/11109-17311/11109
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