Question #51c56

2 Answers
Aug 17, 2017

16x4+232x3+673x2818x+41=0

Explanation:

x÷1x+1x=5÷2

x1x+1x=52

Taking L.C.M

x+1x1x=52

Cross Multiply

2(x+1x)=51x

2x+22x=51x

Collect Like Terms

2x51x=2x+2

Square both sides

(2x51x)2=(2x+2)2

(2x51x)(2x51x)=(2x+2)(2x+2)

4(x)201x+25(1x)=4x2+8x+4

4(x)201x+2525x=4x2+8x+4

201x+2521x=4x2+8x+4

201x=4x2+8x+4+21x25

201x=4x2+29x21

Square both sides

(201x)2=(4x2+29x21)2

400(1x)=(4x2+29x21)2

400400x=(4x2+29x21)(4x2+29x21)

400400x=16x4+232x3+673x21218x+441

Collect like terms

16x4+232x3+673x21218x+400x+441400=0

16x4+232x3+673x2818x+41=0

Solve the polynomial above..

That's how far i could get, But in my own point of view, i strongly doubt the Authenticity of the question..

Aug 17, 2017

See below.

Explanation:

x1x+1x=2.5 Calling y=1x we have

1y+y=2.5y or

1y=(2.5yy)2 or

1y=2.52y5yy+y2 and now making ξ=y we have

ξ45ξ3+(1+2.52)ξ21=0 This polynomial has two real roots

ξ={0.332869,0.43602} giving

y={0.110802,0.190114} and consequently

x={0.889198,0.809886}

but substituting into the original equation only x=0.809886 is feasible, so the solution is

x=0.809886