When $u ( x , y ) = X ( x ) Y ( y )$

question 3

Multiple Choice

When $u ( x , y ) = X ( x ) Y ( y )$ is substituted into the equation $u _ { x } - u _ { y y } = 0$ , the resulting equations for $X$ and $Y$ are

• A) \(X ^ { \prime \prime } + \lambda X = 0 , Y ^ { \prime \prime } + \lambda Y = 0\)
• B) \(X ^ { \prime \prime } + \lambda X = 0 , Y ^ { \prime \prime } - \lambda Y = 0\)
• C) \(X ^ { \prime \prime } - \lambda X = 0 , Y ^ { \prime \prime } + \lambda Y = 0\)
• D) \(X ^ { \prime } + \lambda X = 0 , Y ^ { \prime } + \lambda Y = 0\)
• E) \(X ^ { \prime } + \lambda X = 0 , Y ^ { \prime } - \lambda Y = 0\)

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Definitions:

Electron Transport Chain

A series of complexes that transfer electrons from electron donors to electron acceptors via redox reactions, and couples this electron transfer with the transfer of protons (H+ ions) across a membrane.

Calvin Cycle

A set of biochemical reactions that take place in the stroma of chloroplasts in photosynthetic organisms, resulting in the conversion of carbon dioxide and other compounds into glucose.

Thylakoid Membrane

Membranous sacs located within the chloroplasts of plants, sites of the light-dependent reactions of photosynthesis.

Carbohydrate Molecules

Organic compounds consisting of carbon, hydrogen, and oxygen atoms, serving as a major energy source and structural component of living organisms.