What is a tangent line?

tangent-3.giftangent-2.giftangent-1.gif

7 thoughts on “What is a tangent line?

  1. Joyce,
    tangent line 就是切线! Tangent line is perpendicular to a radius if
    the point is on a circle. The perpendicular line to the tangent line has another name called normal line! Just remember this “a normal line is perpendicular to a tangent line”.
    We can draw a tangent line on a point in any curve! This is an important concept in Chapter 3, 4 and 5 about derivatives (dy/dx).
    In fact, different point on a curve has different tangent line and hence has different gradient. (tangent=gradient on that particular pt.)
    Secant line just an extend to a chord. (a chord has a finite length, a secant line is a long long line.)

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s