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1. Can someone help me with these questions? this is from Edexcel C4 textbook ex.4B and 4c

Find an expression in terms of x and y for dy/dx, given that square root of xy +x+y^2=0.

Find dy/dx of y=xa^x and y=2^x/x
2. It'd be helpful if you could put brackets round stuff mate. I know from Calculus at uni that when differentiating a function including a product xy, treat y as any other constant. Hope that helps
3. There's something called 'implicit differentiation' where you don't start with a y = ...

so you can differentiate xy with respect to x by treating as a product and remembering that you get dy/dx when you differentiate y.

You can do your expression by using product and chain rules. Think of y^2 as a function-of-a-function and use chain rule
4. (Original post by maltsheys)
Find an expression in terms of x and y for dy/dx, given that square root of xy +x+y^2=0.

(Original post by maltsheys)
Find dy/dx of y=xa^x

(Original post by maltsheys)
y=2^x/x

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