1.计算:
(1/3 - 1/5)*(1/5)^-2 除以|-1/3|+(√3 -5)^0 +(-1/4)^2007 *4^2008
读:三分之一减五分之一的差乘五分之一的负二次方除以负三分之一的绝对值加根号三减五的差的0次方加负四分之一的2007次方乘4的2008次方
(过程和理由写清楚)
2.解答
(1)已知A+1/A=3,则A+A^2+1/A^2的直是多少?(过程和理由写清楚)
3.一艘船顺流航行了N千米,用了M小时,如果逆流航速是顺流航速的Q/P倍,那么水流速度是多少? (过程和理由写清楚)
4.已知B+1/C=1,C+1/A=1,且A`B`C均不为零,求AB+1/B的直!
5.计算: X-Y/(Z-X)(Z-Y) - Y-Z/(X-Y)(X-Z) - Z-X/(Y-Z)(Y-X)
注意:?/? 右边的为分母!
大家懂哪题就写哪题,过程写清楚!!
1, (1/3 - 1/5)*(1/5)^-2 除以|-1/3|+(√3 -5)^0 +(-1/4)^2007 *4^2008=2/15×25÷1/3+1+(-1/4×4))^2007 ×4 =10+1-4=7
2, ∵ A+1/A=3 ∴ A^2+1/A^2=9-2=7 (两边同时平方)
3 ,v顺=N/M=v船+v水 (1) v逆=v船-v水=NQ/MP (2) (1)-(2)得:v水=N/2M(1-Q/P)
5, X-Y/(Z-X)(Z-Y) - Y-Z/(X-Y)(X-Z) - Z-X/(Y-Z)(Y-X)
= X-Y/(Z-X)(Z-Y)+Y-Z/(X-Y)(...全部
1, (1/3 - 1/5)*(1/5)^-2 除以|-1/3|+(√3 -5)^0 +(-1/4)^2007 *4^2008=2/15×25÷1/3+1+(-1/4×4))^2007 ×4 =10+1-4=7
2, ∵ A+1/A=3 ∴ A^2+1/A^2=9-2=7 (两边同时平方)
3 ,v顺=N/M=v船+v水 (1) v逆=v船-v水=NQ/MP (2) (1)-(2)得:v水=N/2M(1-Q/P)
5, X-Y/(Z-X)(Z-Y) - Y-Z/(X-Y)(X-Z) - Z-X/(Y-Z)(Y-X)
= X-Y/(Z-X)(Z-Y)+Y-Z/(X-Y)(z-X)-Z-X/(Z-Y)(X-Y)=(X-Y)^2/(X-Y)(Z-X)(Z-Y)-(Z-Y)^2/(X-Y))(Z-X)(Z-Y) -(Z-X)^2/(X-Y))(Z-X)(Z-Y) =(-2XY+2YZ+2XZ)/ (X-Y))(Z-X)(Z-Y)
4 ,ZUO BU CHENG 。
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