xy^2+xy=8x then by points (1,2) what is dy/du?

xy^2+xy=8x then by points (1,2) what is dy/du?

Explanation

You gave the equation:  

xy² + xy = 8x  

We are to find dy/dx at the point (1, 2).


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Step 1: Differentiate both sides implicitly with respect to x:


d/dx(xy²) + d/dx(xy) = d/dx(8x)


Use product rule:  

d/dx(xy²) = x·d/dx(y²) + y²·d/dx(x) = x·2y·dy/dx + y²  

d/dx(xy) = x·dy/dx + y  

d/dx(8x) = 8


So the full derivative becomes:  

x·2y·dy/dx + y² + x·dy/dx + y = 8


Now plug in x = 1, y = 2:


1·2·2·dy/dx + 4 + 1·dy/dx + 2 = 8  

=> 4·dy/dx + 4 + dy/dx + 2 = 8  

=> 5·dy/dx + 6 = 8  

=> 5·dy/dx = 2  

=> dy/dx = 2/5