Question

solve the equation: x+2x^1/2-4=0

Answer 1

let u=x^(1/2)

u^2 +2u -4 =0

Answer 2

k

Answer 3

i dont know where to go from there

Answer 4

quadratic formula, or completing the sqaure

Answer 5

so u^2 + 2u = 4

u^2 +2u +1 = 4+1
(u+1)^2 = 5

Answer 6

u+1 = +_sqrt(5)

Answer 7

u = -1 +- sqrt(5)

Answer 8

so sqrt(x) = -1 + sqrt(5) and sqrt(x) =-1-sqrt(5)

Answer 9

so the first equation gives x= ( sqrt(5) -1 )

and the second eqn gives no solution ( a sqrt cannot be negative )

Answer 10

ok i got it now