Calculate the R-value of a thermal window made of two single panes of glass each 0.100 in. thick and separated by a 0.325-in. air space. (Take the R-value of a 3.5 in. air space to be 1.01 ft2 · °F · h/Btu, and the R-value for 0.100 in. thick glass to be 0.712 ft2 · °F · h/Btu.) (b) By what factor is the transfer of energy by heat through the window reduced by using the thermal window instead of the single-pane window? Include the contributions of inside and outside stagnant air layers.

we have been given a quadratic function and we need to restrict the domain such that it becomes a one to one function.

we know that vertex of this quadratic function occurs at (5,2).

further, we know that range of this function is .

if we restrict the domain of this function to either or , it will become one to one function.

let us know find its inverse.

upon interchanging x and y, we get:

let us now solve this function for y.

hence, the inverse function would be if we restrict the domain of original function to and the inverse function would be if we restrict the domain to .

inverse v=i*r

nice nice