4. Heat is generated with the rate of (x)=aT(x) +b per unit volume of a slab where a & b are non-zero constants, and T' is the local temperature within the slab. The thermal conductivity is k, and slab thickness is L. One side of this slab (x =0) is insulated while its other side (x=L ) is maintained at a constant temperature (T=T). Under steady state, the Fourier equation for heat conduction for this system is: dT -k. = q (x) dx Find an expression for the temperature distribution inside this slab as a function of x. insulated L X T=TL