Mam, actually the question I specified is in the exercise 7.3: Q.NO - 22 307 and this method of multiplying and dividing with sin(a-b) is also given in TOPPER NCERT solutions. I want to know the reason behind multiplying and dividing the integrand with sin(a-b) and also another method to to solve this problem as an alternative.. Please help me..

Asked by damarlasumanjali | 29th Jun, 2015, 08:19: PM

Expert Answer:


Thanks for asking us a question in Ask the Expert section of
There may be umpteen number of methods to solve a problem.

The solution we provided is the easiest one.
We can multiply and divide some constants inside the integrand to get a clear solution.
Here, we are manipulating the integrand in such a way that the denominator in the integrand should separate out into single terms, so that it will
be easy for us to integrate.
There is no other logic behind.
Practice makes perfect. If you practice more problems like this, we can assure you that you will score very good marks in your exams.
All the best!!!!!


Topperlearning Team.

Answered by Vimala Ramamurthy | 29th Jun, 2015, 09:04: PM

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