Ask Singapore Homework?

Upload a photo of a Singapore homework and someone will email you the solution for free.



Question

secondary 3 | A Maths
One Answer Below

Anyone can contribute an answer, even non-tutors.

Answer This Question
Skr
Skr

secondary 3 chevron_right A Maths chevron_right Singapore

I need help for 3b!thankyou!

Date Posted: 5 years ago
Views: 208

See 1 Answer

done {{ upvoteCount }} Upvotes
clear {{ downvoteCount * -1 }} Downvotes
Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
1st
There is no need to expand the bracket fully.

All we need to do is to write down the general term in the expansion and then collect all powers of x together. Different values of r will give all the different powers of x in the expansion. In your case, for the term independent of x, we obtain r = 4.

We need to substitute this value of r into the required coefficient of x (or the constant if the term is independent of x, as is this case) and equate it to the given number.