What is the number of integral values of "k" for which the equation has two rational solutions.

Asked by  | 2nd Apr, 2008, 12:05: PM

Expert Answer:

 

Dear Student,

For the given quadratic equation 2x2 + kx -4 = 0 will have rational solution if the Discriminant D = √b2 – 4ac should be an integer i.e  b2 – 4ac should be a perfect square.i.e k2 -4*2*(-4) = k2 + 32 ,so for k = +2 and -2 the expression will have two rational solution therefore k can take two integral values.

 

 

Answered by  | 7th Jul, 2008, 09:10: PM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.