A point is moving along the graph of the given function at the rate Dx/dt . Find dy/dt for the given values of x. Y= 2x^2+5; dx/dt =3 (A) x=-1 (B) x=0 (C)x=1

Question

(a) x=-1 (b)x=0 (c) x=1

Answer 1

y = 2x² + 5

 

dy/dt = 4x (dx/dt)

 

dx/dt = 3 

 

dy/dt = 4x (3) = 12x

 

Now just substitute the 3 given values of x. By the way, the point moves along the x axis at a rate dx/dt, which is not the same as the rate along the curve.