Question

if x²-4x=1 , and x not equal to zero, find values of x+1/x and x-1/x plz help it's urgent plz​

Answer 1

x²-4x=1

x²-4x-1=0

comparing about equation with a²+bx+c=0,we get

a=1,b=-4, c=-1

x=[-b±√(b²-4ac)]/2a

x=[4±√(16+4)]/2

=[4±√(20]/2

=(4±2√5)/2

x=2+2√5 or x=2-2√5

(x+1)/x=(2+2√5+1)/(2+2√5)

≈1.15

(x-1)/x=(2+2√5-1)(2+2√5)

≈0.85