A)(m/m-1 - 1)* mn-n/m b)4a²-9/9a²-6a+1 : 2a-3/3a-1 + 4-a/1-3a в)(x²-5x/x²-10x+25 + 25/x²-25)* 5+x/125-x³ где-/ это дробь 50

1
1)m/(m-1)-1=(m-m+1)/(m-1)=1/(m-1)
2)1/(m-1)*n(m-1)/m=n/m
2
1)(2a-3)(2a+3)/(3a-1)²*(3a-1)/(2a-3)=(2a+3)/(3a-1)
2)(2a+3)/(3a-1)-4/(3a-1)=(2a+3-4)/(3a-1)=(2a-1)/(3a-1)
3
1)x(x-5)/(x-5)²+25/[(x-5)(x+5)]=x/(x-5)+25/[(x-5)(x+5)]=
=(x²+5x+25)/[(x-5)(x+5)]
2)(x²+5x+25)/[(x-5)(x+5)]*(x+5)/[(5-x)(25+5x+x²)]=-1/(x-5)²