Question

Find the value of the discriminant of the following equations -

$x^2+2x+4=0$

Answer 1

Step 1: Compare with the general equation

$x^2+2x+4=0$

Compare with the general equation

$$\begin{gathered} a{x}^2+bx+c=0 \\ a=1,b=2,c=4 \end{gathered}$$

Step 2: Find the discriminant of the equation

Put the value of a, b, and c in the formula of discriminant

$$\begin{gathered} d=b^2-4ac \\ d=2^2-4\times 1\times 4 \\ d=4-16 \\ d=-12 \end{gathered}$$

Hence the discriminant of the equation ${\mathit{x}}^{\mathbf{2}}\mathbf{+}\mathbf{2}\mathit{x}\mathbf{+}\mathbf{4}\mathbf{=}\mathbf{0}$ is $\mathit{d}\mathbf{=}\mathbf{-}\mathbf{12}\mathbf{.}$