Question

Please help me! Problem is in the comments

Answer 1

So wait when x= 2 the answer is -8/25 and when x= -2 the answer is 8/25?

Answer 2

Sorry,at last in second case,If x=-2....I have typed If x=2

Answer 3

ya

Answer 4

From the Chain Rule, \[\frac{dy}{dt}=\frac{dy}{dx}\frac{dx}{dt}.\] As \[\frac{dx}{dt}\] is given, it remains to calculate \[\frac{dy}{dx}\]. This is done using the quotient rule: \[\frac{dy}{dx}=\frac{-2x}{(1 + x^2)^2}\].

So \[\frac{dy}{dt}=\frac{dy}{dx}\frac{dx}{dt}=\frac{dy}{dx}=\frac{-2x}{(1 + x^2)^2}\cdot (2)=\frac{-4x}{(1 + x^2)^2}\]. Now substitute in \[x=2\] and \[x=-2\] to obtain the solutions.