The first derivative of a curve at any point gives the slope of the tangent at that point.

Here the curve is defined by f(x) = x^2 - 2x + 2

f'(x) = 2x - 2

As the tangent is perpendicular to the the line 4y - x - 5 = 0, it has a slope that is the negative reciprocal of the slope of the line.

4y - x - 5 = 0

=> y = x/4 + 5/4

The slope of the line is 1/4. The slope of the tangent is -4

So 2x - 2 = -4

=> 2x = -2

=> x = -1

For x = -1, f(x) = (-1)^2 + 2 + 2 = 5

Therefore the coordinates of the tangential point are **(-1,5)**

## See eNotes Ad-Free

Start your **48-hour free trial** to get access to more than 30,000 additional guides and more than 350,000 Homework Help questions answered by our experts.

Already a member? Log in here.