Derivatives: Product Rule for y=4-x^2sinx

JimmyA
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Homework Statement


find the dy/dx of y= 4- x (to the 2nd power) sin x


Homework Equations


is there a rule?


The Attempt at a Solution


nothing
 
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Is it 4 - (x^2*sin(x)) or ((4-x)^2 * sin(x))?

You will need the product rule for the first case, or for the second case a combination of the product rule and the chain rule.

Product rule: f'(x) * g(x) + g'(x) * f(x)
Chain rule: f'(g(x)) * g'(x)
 


Ok, per the visitor message I got from you..you don't understand how to use the product rule.

Use the following information:
Let f(x) = x^2 and g(x) = sin(x). The derivative of sin(x) is cos(x) - memorize this. Use the power rule for the derivative of x^2.

f'(x) refers to the derivative of f(x), and g'(x) refers to the derivative of g(x). You should now be able to use the product rule to calculate the derivative.

If you need more help someone else will have to help you, I have to leave now.
 


thank you very much
 
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