Question

数学题（求高手，要过程，会采纳！！！）

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Answer 1

1、原式=9x²y²-1+8x²y²
=x²y²-1

2、原式=(9m²+6mn+n²-n²)÷m
=(9m²+6mn)÷m
=9m+6n

3、原式=-6a³b³c+4a²b³c

4、原式=167²-(167+2)(167-2)
=167²-167²+4
=4

5、原式=x²/4-xy+y²-x²/4+y²/4
=5/4y²-xy

6、原式=(2x+y+2x-y)(2x+y-2x+y)÷xy
=4x·2y÷xy
=8

Answer 2

(3xy+1)(3xy-1)-8x^2y^2=x^2y^2-1
[(3m+n)^2-n^2]/m=(9m^2+6mn+n^2-n^2)/m=9m+6n
-2a^2b(3ab^2c-2bc^2)=-2a^2b^3(3a-2)
167^2 - 169*165 = 167*167-(167+2)*165=167(167-165)-2*165=0
(1/2 x-y)^2-1/4(x^2-y^2)=5/4 y^2 - xy
[(2x+y)^2-(2x-y)^2] / xy =(2x+y+2x-y)(2x+y-2x+y)/xy=4x*2y/xy=8