Question
Is $0.2$ a root of the equation $x^2 – 0.4 = 0$? Justify.
✓
Answer
If 0.2 is a root of equation $x^2 - 0.4 = 0$, then 0.2 must satisfy the given equation.
$x^2 - 0.4 = 0$ [given]
$\Rightarrow (0.2)^2 - 0.4 = 0$
$\Rightarrow 0.04 - 0.4 = 0$
$\Rightarrow\ -0.36\neq0$
So, 0.2 is not a root of the given equation.
$x^2 - 0.4 = 0$ [given]
$\Rightarrow (0.2)^2 - 0.4 = 0$
$\Rightarrow 0.04 - 0.4 = 0$
$\Rightarrow\ -0.36\neq0$
So, 0.2 is not a root of the given equation.
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