Question

Evaluate by using suitable identities: 203 × 205​

Answer 1

Answer:

41615

Step-by-step explanation:

Identity » (a-b)(a+b) = a²-b²

203 × 205

= (204-1) × (204+1)

= (204)² - (1)²

= 41616 - 1

= 41615

Answer 2

Given:

• 203×205

To Find:

• The value of the given equation.

Solution:

let,

203×205 → {equation 1}

We are converting the above equation in the form,

⇒ (a-b)(a+b) = $a^2-b^2$

Here a = 204 and b = 1

Therefore equation 1 becomes,

203×205 = (204-1)×(204+1)

⇒ 203×205 = $204^2-1^2$ = 41616-1

In the above equation, we are first squaring the term and then subtracting them.

⇒ 203×205 = 41615 {multiplying the terms}

∴ The value of the given equation = 41615