1
1)1/(a+b)²-1/(a-b)²=[(a-b)²-(a+b)²]/(a²-b²)²=(a²-2ab+b²-a²-2ab-b²)/(a²-b²)²=
=-4ab/(a²-b²)²
2)-4ab/(a²-b²)²* (a²-b²)/ab=-4
2
1)(a^-5-5)(a^-5+5)/a^-5 * 1/(a^-5 +5)=(a^-5 -5)/a^-5
2)(a^-5 -5)/a^-5 -(a^-5 +5)/a^-5=(a^-5 -5-a^-5 -5)/a^-5=-10/a^-5=-10a^5=
=-10*(-2/5)^5=-10*(-32/3125)=64/625=0,1024