Question

X的平方+X的平方分之25-26=0,解方程

Answer 1

x^2+25/x^2-26=0

x^4-26x^2+25=0

(x^2-1)(x^2-25)=0

(x+1)(x-1)(x+5)(x-5)=0

x1=-1,x2=1,x3=-5,x4=5