(2-(x-3)^(1/2))/(x^2-49)
=((2-(x-3)^(1/2))*(2+(x-3)^(1/2)))/((x^2-49)*(2+(x-3)^(1/2)))
= (7-x)/((x-7)(x+7)((2+(x-3)^(1/2)))
= -1/((x+7)(2+(x-3)^(1/2))
=>
limx->7 (2-(x-3)^(1/2))/(x^2-49)
=
-1/((7+7)(2+(7-3)^(1/2))
=-1/56
(2-(x-3)^(1/2))/(x^2-49)
=((2-(x-3)^(1/2))*(2+(x-3)^(1/2)))/((x^2-49)*(2+(x-3)^(1/2)))
= (7-x)/((x-7)(x+7)((2+(x-3)^(1/2)))
= -1/((x+7)(2+(x-3)^(1/2))
=>
limx->7 (2-(x-3)^(1/2))/(x^2-49)
=
-1/((7+7)(2+(7-3)^(1/2))
=-1/56