Question #8a726

1 Answer
Jan 8, 2018

See below.

Explanation:

To find the instantaneous rate of change, we need to find the derivative of 1/x. Putting in values of x will give us the gradient of the tangent at that point. This is different from the average rate of change, which is the gradient of the secant line that joins 2 points.

So the instantaneous rate of change is given by f'(a), and the average rate of change on an interval [a,b] is given by

((f(b))-(f(a)))/(b-a)

1/x=x^-1

Using the power rule:

dy/dx(x^n)=nx^(n-1)

dy/dx(x^-1)=-x^(-2)=-1/x^2

:.

x_0=2

f'(x_0)=-1/(2)^2=color(blue)(-1/4)

x_1=3

f'(x_1)=-1/(3)^2=color(blue)(-1/9)

Instantaneous Rate of Change:

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Average Rate of Change:

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