Circle a triangle whose base has the length of the circle's circumference and whose height equals the circle's radius, which comes to multiplied by the radius squared: Equivalently, denoting diameter by "d", that is, approximately 79% of the circumscribing square (whose side is of length "d"). The circle is the plane curve enclosing the maximum area for a given arc length. This relates the circle to a problem in the calculus of variations, namely the isoperimetric inequality. Equation of a circle<br> In an "x"–"y" Cartesian coordinate system, the circle with centre coordinates ("a", "b") and radius "r" is the set of
What a piece of work is a man What a piece of work is a man "What a piece of work is man!" is a phrase within a soliloquy by Prince Hamlet in William Shakespeare's play of the same name. Hamlet is reflecting, at first admiringly, and then despairingly, on the human condition. The soliloquy, spoken in the play by Prince Hamlet to Rosencrantz and Guildenstern in Act II, Scene 2, follows in its entirety. Rather than appearing in blank verse, the typical mode of composition of Shakespeare's plays, the speech appears in straight prose: Hamlet is saying that although humans may appear to think and act "nobly"