exercises3 - Partial derivatives and tangent plane Find an...

Partial derivatives and tangent plane
Find an equation of the tangent plane to the given surface at the specified
point.
(1) f ( x, y ) = x
3
+ 2 xy - y + 3, P
0
= (1 , 2 , 6)
(2) f ( x, y ) = e
y
+ x + x
2
+ 6, P
0
= (1 , 0 , 9)
(3) f ( x, y ) =
√
x - y , P
0
= (5 , 1 , 2)
(4) ln(2 x + y ), P
0
= ( - 1 , 3 , 0)
(5) e
x + y
cos(