Find the Directional Derivative of the Function $f ( x , y ) = x ^ { 2 } + y ^ { 2 }$

question 274

Multiple Choice

Find the directional derivative of the function $f ( x , y ) = x ^ { 2 } + y ^ { 2 }$ at the point $( 1,2 )$ in the direction $\theta = \frac { \pi } { 2 }$ .

• A)0
• B)1
• C)2
• D)3
• E)4
• F)5
• G)6
• H)7

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A hormone secreted by the pineal gland that plays a major role in regulating sleep-wake cycles and circadian rhythms.

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The inability to get to sleep, stay asleep, or get a good quality of sleep.

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