Page 215 - Schaum's Outline of Theory and Problems of Advanced Calculus
P. 215
206 APPLICATIONS OF PARTIAL DERIVATIVES [CHAP. 8
2
2
2
[Hint: For (a)use the fact that the quadratic form A þ B þ C
þ 2D þ 2E
þ 2F
> 0 (i.e., is
positive definite)if
A D
F
A D
A > 0; > 0; D B E > 0
D B
F E C
