Can gauss save us?

The surface charge density $$\sigma$$ of a non conducting disc of radius 'R' varies as $$\sigma = br$$ , where b is a positive constant and r is the distance from the centre of the disc.

Find the electric field caused by the disc at a point along the axis of the disc and a distance x from its centre.

Details and assumptions :

Find the absolute value of electric field at distance in SI units.

$$R = x = 1 m$$

$$b = 10^{-9} \dfrac{C}{m^{3}}$$

$$\dfrac{1}{4 \pi \epsilon_{0}} = 9\times 10^{9} \dfrac{Nm^{2}}{C^{2}}$$

$$\epsilon_{0}$$is permittivity of free space.