Question

用配方法怎么解?2x^2+x=10

Answer 1

配方就是配成平方的算式：

x^2+x/2+1/16=5+1/16=81/16

(x+1/4)^2 = 81/16

x+1/4 = +/-(9/4)

x1 = 2;

x2 = -5/2 = -2.5.