题目

一,计算
1,(X+Y/2)^2+(X-Y/2)^2
2,(7A-B-1)(7A+B-1)
二,已知A+B=5,AB=-6,求下列各式的值
1,A^2+B^2
2,A^2-AB+B^2
三,计算
(-12X^3*Y^4*Z)/(-4X^2*Y^3*Z)
(-1/4*A^6*B^4*C)/(2*A^3*C)
(2M^N+1)/(8M^2N+1)
6(A-B)^5/1/3(A-B)^2
(3A)^3*B^2/(8B^3*B^2)
3A^M+1*B^B+1/(-1/3A^MB^N-20*(1/9B)^2
-1/8A^5*B^4*C^2/(4B^2*B)
5(X-Y)^5/1/5(X-Y)^2
[X(X+1)+X^2*(X-1)]/(-3X)
[(M+N-P)(M+P+N)-(M+N)^2]/(-P)
就这些拉,要正确,

提问时间：2020-12-27

答案

一,计算
1,(X+Y/2)^2+(X-Y/2)^2
=2X^2+0.5Y^2
2,(7A-B-1)(7A+B-1)
=49A^2-14A+1-B^2
二,已知A+B=5,AB=-6,求下列各式的值
1,A^2+B^2
=(A+B)^2-2AB=25+12=37
2,A^2-AB+B^2
=(A+B)^2-3AB=25+18=43
三,计算
(-12X^3*Y^4*Z)/(-4X^2*Y^3*Z)
=3XY
(-1/4*A^6*B^4*C)/(2*A^3*C)
=-1/8*A^3*B^4
(2M^N+1)/(8M^2N+1)
题目错了
6(A-B)^5/1/3(A-B)^2
=18(A-B)^3
(3A)^3*B^2/(8B^3*B^2)
=27/8
3A^M+1*B^B+1/(-1/3A^MB^N-20*(1/9B)^2
有错
-1/8A^5*B^4*C^2/(4B^2*B)
=-1/32*A^5*B*C^2
5(X-Y)^5/1/5(X-Y)^2
=25(X-Y)^3
[X(X+1)+X^2*(X-1)]/(-3X)
=-(1+X^2)/3
[(M+N-P)(M+P+N)-(M+N)^2]/(-P)
=P