quadratic equation question (1 Viewer)

[jkdsfsio3458963]

solve the equation 2x^4+7x^2-4=0 by first reducing it to a quadratic equation

 

[ForbiddenND]

let x^2 = y then its basically a normal quadratic equation and then after you solve it just sub in x^2 where ever y appears

 

[Gibbatron]

Sub in m for x^2

2m^2 + 7m - 4 = 0
2m^2 + 8m - 1m - 4 = 0
2m(m + 4) - 1(m + 4) = 0
(2m - 1)(m + 4) = 0

Sub in m = x^2

2m - 1 = 0
2x^2 - 1 =0

m + 4 = 0
x^2 + 4 = 0

I'm sure you can work out the rest

 

[omniscience]

solve the equation 2x^4+7x^2-4=0 by first reducing it to a quadratic equation

fundamental theorem of addition:

1 + 1 = 2

using this fundamental theorem, u get the answer as