Question

Find the value using algebraic formula.

124 × 126

Answer 1

Given: 124 × 126

124 × 126 = (125 – 1)(125 + 1)

Let 125 = x then (125 – 1) (125 + 1) = (x – 1) (x + 1)

We know that,

(a + b) (a – b) = a² – b²

Hence,

⇒ x² – 1

⇒ 125² – 1

⇒ 15625 – 1

⇒ 15624