Объяснение:
1. 1+(3x+x²)/(x+3)=1+(x*(x+3)/(x+3))=1+x=x+1.
2. (1/(x+1))-x/(1+2x+x²)=(1/(x+1))-x/(x+1)²=(x+1-x)/(x+1)²=1/(x+1)².
3. (x+1)÷1/(x+1)²=(x+1)*(x+1)²=(x+1)³.
Объяснение:
1. 1+(3x+x²)/(x+3)=1+(x*(x+3)/(x+3))=1+x=x+1.
2. (1/(x+1))-x/(1+2x+x²)=(1/(x+1))-x/(x+1)²=(x+1-x)/(x+1)²=1/(x+1)².
3. (x+1)÷1/(x+1)²=(x+1)*(x+1)²=(x+1)³.