- 23
- 25
- 52
- 32

Option 4 : 32

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**Given:**

(a + b) = 16

ab = 63

**Formula Used:**

(a - b)^{2} = (a + b)^{2} - 4ab

**Calculation:**

We know that,

(a - b)2 = (a + b)2 - 4ab

⇒ (a - b)2 = (16)2 - 4 × 63

⇒ (a - b)2 = 256 - 252

⇒ (a - b)2 = 4

⇒ a - b = √4

⇒ a - b = 2

Now, a^{2} - b^{2} = (a + b)(a - b)

⇒ 16 × 2

⇒ 32

**∴ The value of a2 - b2 is 32.**

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