siuyu
幼苗
共回答了24个问题采纳率:91.7% 举报
由题意得:(a-3)²+|b-1|=0
∴a=3,b=1
∴原式=(3-1/3)/4=2/3
第二题顺序没看明白
原式=4/(x²-4)*x²-4/x
=(4x²)/(x²-4)-4/x
=(4x³-4x²+16)/(x²-4)
原式=(x+2- 8/x)/x+1
=(2x+2-8/x)/x
=2+2/x-8/x²
=2+ 2/(3-根号2)-8/(9+2-6根号2)
=2+2(3+根号2)/7 -8(11+6根号2)/49
=2+ (6+2根号2)/7 - (88+48根号2)/49
=(98+42+14根号2-88-48根号2)/49
= (52-34根号2)/49
1年前
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