"A person is eccentric if his behavior deviates from normal. Jesus Christ expects His disciples to be eccentric, since living a Christlike life is not normal in this world (Titus 2:14). Likewise, in mathematics, conic sections are eccentric if they deviate from a circle. Eccentricity is a measure of this deviation. The eccentricity of an ellipse (e) is the ratio of focal distance (c) to the length of the semimajor axis (a): e = c/a. Since c and a are distances and c < a, the eccentricity of any ellipse is 0 < e < 1."
-- Precalculus for Christian Schools by Kathy D. Tilger and Ron Tagliapietra
1 comment:
I don't have a copy of the book. This passage and others from the book are excerpted in the Amazon reviews and, perhaps more reliably, in a Harper's Magazine column from December 2004.
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