Question

通分(1).2a分之-5 ,9a的平方分之2 ,负12a的4次方b的平方分之7c`

Answer 1

通分

(1).-5/(2a),2/(9a²),-7c/(12a^4b²)

-5/(2a)=-270a³b²/(108a^4b²)

2/(9a²)=24a²b²/(108a^4b²)

-7c/(12a^4b²)=-63c/(108a^4b²)

(2).1/(x+2),x²-4x/4,2-2/x

1/(x+2)=x/[x(x+2)]

x²-4x/4=x²(x-1)(x+2)/[x(x+2)]

2-2/x=2(x-1)(x+2)/[x(x+2)]