Multivariable CalculusHardOptimization & Lagrange Multipliers ShareOptimization & Lagrange Multipliers · Hard problemFind the minimum value of f(x,y)=3x2−xy+21x+3y2−21y+63f(x, y) = 3 x^{2} - x y + 21 x + 3 y^{2} - 21 y + 63f(x,y)=3x2−xy+21x+3y2−21y+63.Check Show answer Walk through it step by step Practice more like this Review this concept