Equation of the Tangent Line...2

[nycmathguy]

Find the equation of the tangent line to the curve
y = x^3 - x + 5 at the point P (1, 5).

Let me see.

d/dx [x^3 - x + 5] = 2x^2 - 1.

Let x = 1

2(1)^ - 1 = 2 - 1 = 1

The slope is 1.

y = mx + b

Let x = 1, m = 1, and y = 5.

5 = (1)(1) + b

5 = 1 + b

5 - 1 = b

4 = b

y = mx + b

y = (1)x + 4

y = x + 4

Yes?

 

[MathLover1]

correct

 

[nycmathguy]

correct

Very good. I think Calculus 1 will be fun. However, related rates is a totally different ball game.