1.两边乘以5x:
2.5x^2-0.05x=3
50x^2-x-60=0
x1=[1+√(1+12000)]/100=0.01+√1.2001
x2=0.01-√1.2001
2. x=2(1/30 + 1/x)
15x^2-x-15=0
x1=[1+√(1+900)]/30=(1+√901)/30
x2=(1-√901)/30