How do you solve # x ^ { 2} + \sqrt { 3} x - 6= 0#?

1 Answer
Jul 31, 2017

#x=-2sqrt3# or #sqrt3#

Explanation:

To solve #x^2+sqrt3x-6=0#, there could be two ways, one, by factorizing the quadratic polynomial and two, using completing square method.

For factorizing we should split te middle term #sqrt3# in two parts whose product is #-6#. As #sqrt3#, would be involved these are #2sqrt3# and #-sqrt3#, and hence above becomes

#x^2+2sqrt3x-sqrt3x-6=0#

or #x(x+2sqrt3)-sqrt3(x+2sqrt3)=0#

i.e. #(x-sqrt3)(x+2sqrt3)=0#

i.e. #x=sqrt3# or #-2sqrt3#

Other way could be

#x^2+2xxsqrt3/2xx x-6=0#

or #(x^2+2xxsqrt3/2xx x+(sqrt3/2)^2)-(sqrt3/2)^2-6=0#

or #(x+sqrt3/2)^2-27/4=0#

or #(x+sqrt3/2)^2-((3sqrt3)/2)^2=0#

or #(x+sqrt3/2+(3sqrt3)/2)(x+sqrt3/2-(3sqrt3)/2)=0#

or #(x+2sqrt3)(x-sqrt3)=0#

i.e. #x=-2sqrt3# or #sqrt3#