g′=g(1−hR)g^{\prime}=g\left(1-\frac{h}{R}\right)g′=g(1−Rh)
g′=g(RR−h)g^{\prime}=g\left(\frac{R}{R-h}\right)g′=g(R−hR)
g′=g(R−hR)2g^{\prime}=g\left(\frac{R-h}{R}\right)^{2}g′=g(RR−h)2
g′=g(R−h)g^{\prime}=g(R-h)g′=g(R−h)
g′=g(R+h)g^{\prime}=g(R+h)g′=g(R+h)