Resistance of a resistor at temperature `t^@C` is `R_t =R_0 (1+alphat + betat^2)`, where `R_0` is the resistance at `0^@C`. The temperature coefficient of resistance at temperature `t^@C` is

Explanation

`alpha=(1)/(R).(dR)/(dt)=(I)/(R_(0)(1+at+bt^(2)))[R_(0)(a+2bt)]`
`thereforealpha=((alpha+2bt)/(1+alphat+bt^(2)))`