Let $z = x y + x ^ { 2 } y$

question 192

Multiple Choice

Let $z = x y + x ^ { 2 } y$ , and let $x$ and $y$ be functions of $S$ and $t$ with $x ( 0,0 ) = 1 , y ( 0,0 ) = 2$ , $\delta x / \delta s = 3$ , and $\delta y / \delta s = 4$ at $( s , t ) = ( 0,0 )$ . Find $\delta z / \delta s$ when $( s , t ) = ( 0,0 )$ .

• A)21
• B)22
• C)23
• D)24
• E)25
• F)26
• G)27
• H)28

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Definitions:

Predominant Purpose Test

A legal criterion used to determine the nature of a contract based on its primary objective, especially in determining whether it falls under the sale of goods or the provision of services.

Service

The action of helping or doing work for someone, or a system supplying a public need such as transport, communications, or utilities.

Statute Of Frauds

A legal concept that requires certain types of contracts to be executed in writing and signed by the party to be charged, in order to be legally enforceable.

Void

refers to something that is legally declared to be null and without effect, as if it never existed or happened.