Mathematics: E-book!

Addition, division, subtraction and multiplica...

Addition, division, subtraction and multiplication symbols (Photo credit: Wikipedia)

A noted follower had requested a PDF file of questions/answers. Well, this is even better! The following link is of an e-book of Mathematics by Mr. M. P. Keshari.

PART 1 (Chp 1 to Chp 11):

PART 2 (Chp 12 to Chp 23):

PART 3 (Chp 24 to Chp 29):

It is thorough and even has examples of solved questions. Very useful! Do check it out! 🙂

Mathematics: Important Formulae and Points to Note

Math Mark

Math Mark (Photo credit: Wikipedia)

This PDF file consists of important chapter wise formulae that you will need to remember along with any important points you should keep in mind while preparing for your exam.

The proper credit for these notes has been given in the PDF file itself. Please check it out! It will be very useful to you!

Thank you!

Math: Trigonometric Identities and Tips to Remember

Trigonometry! Some of you may have been practicing trigonometry since 8th grade.. But who really likes trigonometry?

Trigonometry is simple logic and once you get the hang of it, it is a very interesting topic in math! And easy, too!

We all know the basics:

sinA = perpendicular/hypotenuse

cosA = base/hypotenuse

tanA = sinA/cosA

           = perpendicular/base

cotA = 1/tanA

           = cosA/sinA

           = base/perpendicular

sinA = 1/cosecA

cosA = 1/secA

tanA = 1/cotA

Trigonometric Table

Here are the important trigonometric identities you’ll need to memorize (YES, MEMORIZE!):

sin2A + cos2A = 1

1 + tan2A = sec2A

                           To remember this identity, s and t are different letters.

1 + cot 2A = cosec2A

                     To remember this identity, c (cosec) and c (cot) are the same letters and cot is the inverse of tan.

While solving Proving sums in Trigonometry,


If you get a question like this:

P.T. (1+cosA)/(1 – cosA) = (cosecA + cotA)2

Observe that the RHS has cosecA=1/sinA and cotA=cosA/sinA

Since both cosecA and cotA, when simplified have sinA as the denominator, if we divide EACH TERM on the LHS by sinA, we will solve the sum.

You can also apply the same technique to proving sums which have cosA as the denominator.

Give it a try!


Here’s a link to the PDF file for the above notes:

NOTES – Trigonometric Identities and Tips to Remember

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