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I know i use the product rule but I keep getting the wrong answer

I know i use the product rule but I keep getting the wrong answer-example-1
User Alexandre Neukirchen
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1 Answer

12 votes
12 votes

Answer:

dx/dt | (x=3) = 27/2

Step-by-step explanation:

x*y = 2 ......... (a)

At x = 3, (3)*y = 2 => y = 2/3

Differentiate (a) wrt t,

x.dy/dt + y.dx/dt = 0 ........ (b)

Put x=3, dy/dt=-3 and y=2/3 in the differential equation (b),

3(-3) + (2/3)*dx/dt = 0

dx/dt = (9*3)/2 = 27/2

User Domen Vrankar
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2.9k points