Answer:

Step-by-step explanation:
We are given that
Equation of curves


Both curves lie on S.
We have to find the equation of tangent plane at P(4,1,4).


Hence, t=0 and u then it satisfied the given point.
Substitute the values in the derivatives


The equation of tangent at point P(4,1,4) is given by




Let
and
. By the product rule,

By the power rule, we have
and
, but
are functions of
, so we also need to apply the chain rule:


and we have


So we end up with

Replace
to get everything in terms of
:

We can simplify this by factoring:


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