Помогите пожалуйста решить задания 43 а б 44 а б

43a [a²(a+1)-(a+1)]/(a+1)²=(a+1)(a²-1)/(a+1)²=(a²-1)/(a=1)=(a-1)(a+1)/(a+1)=a-1 43б x+x-12=(x+4)(x-3) x1+x2=-1 U x1*x2=-12⇒x1=-4 U x2=3 (x²+x-12)/(x²=8x=16)=(x+4)(x-3)/(x+4)²=(x-3)/9x=4) 44a 1)m+n-4mn/(m+n)=(m²+2mn+n²-4mn)/(m+n)=(m²-2mn+n²)/(m+n)= =(m-n)²/(m+n) 2)m/(m+n)+n/(m-n)-2mn/(m-n)(m+n)=(m²-mn+mn+n²-2mn)/(m²-n²)= =(m²-2mn+n²)/(m²-n²)=(m-n)²/(m-n)(m+n)=(m-n)/(m+n) 3)(m-n)²/(m+n)*(m+n)/(m-n)=m-n 44б 1)(a+b)(a²-ab+b²)/(a+b)*1/(a²-b²)=(a²-ab+b²)/(a²-b²) 2)(a²-ab+b²)/(a-b)(a+b)+2b/(a+b)-ab/(a-b)(a=b)= =(a²-ab+b²+2ab-2b²-ab)/(a²-b²)=(a²-b²)/(a²-b²)=1