1.(a^m+b^n)*[(a^(2m)+b^(2n)]*(a^m-b^n)
= [(a^(2m)-b^(2n)]*[(a^(2m)+b^(2n)]
= a^(4m)-b^(4n)
2.(x-3y)*(x^2+9y^2)*(x+3y)
= (x^2-9y^2)*(x^2+9y^2)
= x^4 - 81y^4
3.(2x-3y)(2x+3y)-(4x+5y)(4x-5y)
= 4x²-9y²-(16x²-25y²)
=-12x²+16y²
4.x-y=5
5.(5/13)^2005 *(2+3/5)^2006-4^1000*(-1/2)^2004
= (5/13)^2005 * (13/5)^2005*(13/5)-2^2000*(-1/2)^2000*(-1/2)^4
= 13/5 -1/16
= 203/80
6.(-1001)^7*(-0.125)^6*(-2/7)^7*(-4/13)^7*(-1/11)^7
= [-1001*(-1/8)*(-2/7)*(-4/13)*(-1/11)]*(-8)
= 8
7.2007*1003