(Bonus Question (10’), need steps to gain points) For the fu…

(Bоnus Questiоn (10’), need steps tо gаin points) For the function ,    (i)     find ; (ii) find the lineаr аpproximation of f(x,y,z) at the point (2,3,4); (iii)  use the linear approximation obtained in (ii) to estimate the number