Search IntMath
Close

450+ Math Lessons written by Math Professors and Teachers

5 Million+ Students Helped Each Year

1200+ Articles Written by Math Educators and Enthusiasts

Simplifying and Teaching Math for Over 23 Years

# Trig graphs - how do you feel today?

By Murray Bourne, 22 Apr 2007

Biorhythms are interesting. There is no science involved, and they should not be taken seriously.

I have added a section in the math site called Biorhythm Graphs. It contains an interactive graph where you can enter your own, or anyone's, birthday and see their biorhythm profile. Check it out.

Biorhythms are interesting because they are examples of trigonometric curves with different periods.

For a skeptical analysis of biorhythm theory, see Skeptik's Dictionary.

### 4 Comments on “Trig graphs - how do you feel today?”

1. Steven says:

What baloney!

There have to be cycles in our emotions (a woman's period is an obvious one).

But this biorhythm stuff is nonsense.

2. alQpr » Blog Archive » squareCircleZ on Biorhythms says:

[...] squareCircleZ Â» Trig graphs - how do you feel today?, Murray Bourne at squareCircleZ has a nice Flash gizmo to show biorhythm graphs and links to a site [...]

Mr. Bourne’s and others’ skepticism is justified in the sense that as mathematicians / scientists, they are unable to affirm that the sine curves would coincide with our actual biorhythms, so that we could derive advantage out of that. Whether it is trying to predict “ our future ” or the “ future prices ” in financial markets − they are equally mythical / truths / unknown / whatever ! Any way, that it is the realm of unknown, and that statistics is a science, medicine is a science, Laplace’s determinism is science, “ butterfly effect is a science ” − why not biorhythms and astrology are so ? This is so, because our life span is not enough to conduct a study, make observations on subjective rather than objective issues, formulate a hypothesis, undertake further study to prove or disprove the validity of that hypothesis to make a theory out of that. It is the complexity of the subject that precludes it from a scientific study [ by current definition of science ].

4. Murray says:

Thanks for the input, madhav. Actually, I'm inclined to believe in some sort of biorhythms, but not as per the graph above.

### Comment Preview

HTML: You can use simple tags like <b>, <a href="...">, etc.

To enter math, you can can either:

1. Use simple calculator-like input in the following format (surround your math in backticks, or qq on tablet or phone):
a^2 = sqrt(b^2 + c^2)
(See more on ASCIIMath syntax); or
2. Use simple LaTeX in the following format. Surround your math with $$and$$.
$$\int g dx = \sqrt{\frac{a}{b}}$$
(This is standard simple LaTeX.)

NOTE: You can mix both types of math entry in your comment.

From Math Blogs