1. Factorization by
identity a2- b2

2. 1. Factorize the following expression by using an identity.
p2 – Tip : 9 = 3²
So, p2 – 9 = p² - 3²
a2 - b2 = (a + b)(a - b)
So, a = p and b = 3.
Factorizing p2 – 9 using a2 - b2 = (a + b)(a - b) identity we get
∴ p2 – 9 = (p + 3) (p - 3) Substituting a = p and b = 3 in (a + b)(a - b)

3. 2. Factorize the following expression by using an identity.
4p2 – Tip : 4 = 2² and 49 = 7²
So, 4p2 – 49 = 22p² - 7² = (2p)2- 7²
a2 -b2 = (a + b)(a - b)
So, a = 2p and b = 7.
Factorizing 4p2 – 49 using a2 - b2 = (a + b)(a - b) identity we get
∴ 4p2 – 49 = (2p + 7) (2p - 7) Substituting a = p and b = 3 in (a + b)(a - b)

4. Try These Factorize the following expression by using identities :