1. m/(m²-16m+64)=m/(m²-2*8*m+8²)=m/(m-8)².
2. (m+4)/(m²-64)=(m+4)/((m-8)(m+8)).
3. (m/(m-8)²-(m+4)/((m-8)(m+8))=(m*(m+8)-(m+4)(m-8))/((m-8)²*(m+8))=
=(m²+8m-m²+4m+32)/((m-8)(m-8)(m+8))=(12m+32)/((m-8)(m-8)(m+8))=
=4*(3m+8)/((m-8)(m²-64)).
4. (4*(3m+8)/((m-8)(m²-64)):((3m+8)/(m²-64))≡4/(m-8).
А. ax-ay+bx-by=a(x-y)+b(x-y)=(x-y)(a+b)
б. 2x+7y+14+xy=(2x+xy)+(7y+14)=x(2+y)+7(y+2)=
=(y+2)(x+7)
в. 2x-ac-cx+2a=(2x+2a)-(ac+cx)=2(x+a)-c(a+x)=
=(x+a)(2-c)
D = -15 + 19 = 4
<span>a81 = -19 + 80*4 = 320 - 19 = 301
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