NCERT Class 9 Solutions: Polynomials (Chapter 2) Exercise 2.4 – Part 2
Q3 Find the value of k, if is a factor of in each of the following cases:
Solution:

According to factor theorem, if is a factor of , then

Then,

Then,

Then,

Then,
Q4 Factorize:
Solution:
Q5 Factorize:
Solution:

Let us guess a factor and choose value of a arbitrarily as 1.
Now, putting this value in
So, is a factor of
Now,
So,

Let us guess a factor . A should be a factor of 5
Therefore,
For
So, is not a factor of
For
So, is a factor of
Now,
So,

Let us guess a factor . A should be a factor of 20
Therefore,
For
So, is not a factor of
For
So, is a factor of
Now,
So,

Factors of are
For
So, is not a factor of
Now,
So,