Thread: Angle problem: Changing algebric expressions to angles
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Old July 3rd, 2009, 05:47 PM
chengbin chengbin is offline
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In a line y=mx+b, m=\tan \theta,\theta is the angle between the line and the positive direction of the x-axis.

Here is a formula for you.

Given that \theta is the angle formed from the line y=mx+b to line y=m'x+b', then

\tan\theta=\frac {m'-m}{1+mm'}
Last edited by chengbin; July 4th, 2009 at 07:49 AM.
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