Porfavor ayudenema sacar el dominio de estas funciones?

A) <img src="https://tex.z-dn.net/?f=4-%20%20%5Cfrac%7B1%7D%7Bv%5E2%7D%20%3D0" />

4 = \ frac{1}{v ^ 2}

<img src="https://tex.z-dn.net/?f=4v%5E2%3D1" />

<img src="https://tex.z-dn.net/?f=%282v%29%5E2%3D1" />

<img src="https://tex.z-dn.net/?f=2v%3D%20%5Csqrt%7B1%7D%20" />

<img src="https://tex.z-dn.net/?f=v%3D%20%28%20%5Cfrac%7B%2B%7D%7B-%7D%201%29%2F2" />

b)

<img src="https://tex.z-dn.net/?f=5-%20%5Csqrt%7Bw%7D%20%3D0" />

<img src="https://tex.z-dn.net/?f=5%3D%20%5Csqrt%7Bw%7D%20" />

<img src="https://tex.z-dn.net/?f=5%5E2%3Dw" />

25 = w

a) Reales menos + / - 1 / 2 o ( - infinito ; - 1 / 2)u( - 1 / 2 ; 1 / 2)u(1 / 2 ; + infinito)

b) Reales menos 25 ( - infinito ; 25)u(25 ; + infinito).