document.write( "Question 1039247:  When an expression is real for all values of x, the why is it discriminant always less than 0. 
\n" );
document.write( "I was solving this question :
\n" );
document.write( "The values of a for which the expression (ax^2 + 3x -4 )/(3x - 4x^2 +a ) assumes all real values for real values of x, belongs to: ?\r
\n" );
document.write( "\n" );
document.write( "It would be more helpful to me if anyone can explain me the reason graphically?\r
\n" );
document.write( "\n" );
document.write( " \n" );
document.write( "
Algebra.Com's Answer #654009 by josgarithmetic(39630)    ![]() You can put this solution on YOUR website! Your numerator and your denominator both have roots or zeros; but remember that your rational expression will not accept its roots in its denominator. \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "An expression with no real roots will not intersect the x-axis.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Try solving a quadratic equation using Completing the Square. You will find an expression occurring called discriminant. Look at the lesson done all in symbols but no graph is present: Completing the Square to Solve Quadratic Equation -- https://www.algebra.com/my/Completing-the-Square-to-Solve-General-Quadratic-Equation.lesson?content_action=show_dev\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Real solutions require the discriminant to be NON-ZERO; otherwise, solutions are complex with imaginary components; or, the roots are complex with imaginary components. \n" ); document.write( "  |