Consider an equation
$\large \rm y = \frac{ax+b}{cx^2+dx+e} $

If I have to find the range of y, according to a new method, I should arrange the whole equation in a quadratic equation in terms of x and y. Then I have to set $discriminant

Question

Consider an equation 
$\large \rm y =  \frac{ax+b}{cx^2+dx+e} $

If I have to find the range of y, according to a new method, I should arrange the whole equation in a quadratic equation in terms of x and y. Then I have to set $discriminant<0$  to find out the range of y. Can somebody explain me the last step? Why do we set discriminant to less than 0?

faiqraees · Answer

@ganeshie8

jiteshmeghwal9 · Answer

i guess discriminant should be greater than 0

jiteshmeghwal9 · Answer

to find range as a set consisting of real numbers.

faiqraees · Answer

Try solving this

"Show that there are no points on C for which 0<y<8 where curve C is $\large \rm y=\frac{x^2}{x-2}$" using your discriminant >0 approach.

faiqraees · Answer

@jiteshmeghwal9

jiteshmeghwal9 · Answer

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