Escitalopram is an oral drug that is used for treating depression and generalized anxiety disorder. Chemically, escitalopram is similar to citalopram . Both are in a class of drugs called selective serotonin reuptake inhibitors (SSRIs), a class that also includes fluoxetine , paroxetine and sertraline .
1 A circle is all of the points that are a fixed distance, known as the radius, from a given point, known as the center of the circle. 2  Explore the standard equation of a circle using the applet below (Go here for a larger version).
Example:A parametric equation for a circle of radius 1 and center (0, 0) is: x = cos t, y = sin t. The equations x = f (t), y = g (t) are called parametric equations .Given a parametric curve, sometimes we can eliminate t and obtainanequivalentnon-parametricequationforthesamecurve.