To solve the equation \(2y^2 - 1 = 0\), follow these steps:
Add 1 to both sides of the equation: \[ 2y^2 = 1 \]
Divide both sides by 2: \[ y^2 = \frac{1}{2} \]
Take the square root of both sides: \[ y = \pm \sqrt{\frac{1}{2}} \]
Simplify the square root: \[ y = \pm \frac{\sqrt{2}}{2} \]
So the solutions are \(y = \frac{\sqrt{2}}{2}\) and \(y = -\frac{\sqrt{2}}{2}\).