An Introduction to Mathematics
Notes
Excerpts
Notes
In reading these equations it must be noted that a bracket is used in mathematical symbolism to mean that the operations within it are to be performed first. Thus $(1 + 3) + 2$ directs us first to add $3$ to $1$, and then to add $2$ to the result; and $1 + (3 + 2)$ directs us first to add $2$ to $3$, and then to add the result to $1$.
Notes
We perform first the operations in brackets and obtain 2 × 7 = 6 + 8 which is obviously true.
Notes
This fundamental ratio $\dfrac{SP}{PN}$ is called the eccentricity of the curve.
Notes
An ellipse with small eccentricity is very nearly a circle, and an ellipse of eccentricity only slightly less than unity is a long flat oval.
Notes
But it is possible for a series with terms partly positive and partly negative to be convergent, although the corresponding series with all its terms positive is divergent.
Notes
Such convergent series, which are not absolutely convergent, are much more difficult to deal with than absolutely convergent series.
Equations
- This equation is in Conic Sections (Conic Sections)
Problems
No exercises in this chapter.