Number theory takes a new turn with the introduction of rational and irrational numbers in addition to natural numbers, whole numbers, and integers. Laws of exponents are revisited.
Algebra deals with a detailed explanation of polynomials, linear equations in one variable and two variables, zeros of a polynomial remainder, and factor theorems and algebraic identities.
The basics of coordinate geometry are introduced with respect to the Cartesian plane.
Euclid’s geometry explains obvious notions, axioms, postulates, and theorems. Other aspects of geometry are covered under parallel lines, the related angles, triangles, congruence, and certain theorems related to triangles, quadrilaterals, basic areas of parallelograms, and triangles and circles.
Mensuration: this entails the calculation of surface areas and volumes of 3D objects like cubes, cuboids, spheres, hemispheres and right circular cylinders and cones.
Statistics is very basic and introductory which includes a collection of data and its presentation, making simple bar graphs, histograms, and frequency polygons. It also includes the definition of mean, median and mode of ungrouped data.
To help CBSE grade 9 Mathematics students, the teachers of Edugraff ensure a smooth and seamless transition to the new concepts of this class by following the traditional concepts of building the unknown on the known. Teaching of new topics like coordinate geometry, algebraic identities and probability is done using repetitive drills and teaching aids. This pre-board year is supplemented by the derivation of formulas and their applications.
Students get acquainted with certain new ideas which lay the cornerstone for Mathematical concepts which are used all the way. Spatial understanding is enhanced by learning how to construct certain regular polygons and about the relationships between various geometrical shapes.
What advice do you have for a 9th grader?
This is the time to indulge in a lot of academic as well as co-scholastic activities since the syllabus is quite relaxed. It is a good idea to polish your skills by participating in competitions that challenge you like the Olympiads, Talent Search competitions, etc. It prepares you well for the next classes too.
Should I practice from some other source besides the NCERT Mathematics? If yes, which book should I use?
Yes. Extra practice always helps. You could practice from Mathematics class 9 by R.S. Aggarwal or by R.D. Sharma. They have plenty of solved examples which are useful.