3 и 4 Вариант!!!!Пожалуйста!!!ДАМ 60 БАЛЛОВ

А)(a-3)²/(1-b)(1+b+b²) *(b-1)(b+1)/2(a-3)=(3-a)(b+1)/(2(1+b+b²)б)a(a+b)/(a-b)(a+b)*(a-b)(a²+ab+b²)/ab(b+a)=(a²+ab+b²)/b(a+b)в)1)3a-6a²/(2a-5)=(6a²-15a-6a²)/(2a-5)=15a/(5-2a)2)15a/(5-2a)*(5-2a)²/3a(a²-25)=5(5-2a)/(a²-25)г)(1+x)²/(x-1)²*4(x-1)/3(x+1)=4(x+1)/3(x-1)а)(3-x)²/(4x²-6x+9)*(3+2x)(4x²-6x+9)/2(3-x)=(3-x)(3+2x)/2б)(x-y)(x+y)(x²+y²)/(x-y)²*(x-y)/x(x+y)=(x²+y²)/xв)1)(m-n)/(m+n)-(m³-n³)/(m+n)(m²-mn+n²)==(m³-m²n-m²n+mn²+mn²-n³-m³+n³)/(m+n)(m²-mn+n²)==(2mn²+2m²n)/(m+n)(m²-mn+n²)=2mn(n-m)/(m+n)(m²-mn+n²)2)(m-n)/(m+n)+(m²+n²)/(m-n)(m+n)=(m²-2mn+n²+m²+n²)/(m-n)(m+n)==2(m²-mn+n²)/(m-n)(m+n)3)2mn(n=m)/(m+n)(m²-mn+n²) * 2(m²-mn+n²)/(m-n)(m+n)=-2mn/(m+n)²г)(4-a)(4+a)/2(7+b)*3(b+7)/3(4-a)=(4+a)/2