Question

use identity and factorise the following.
best answer will be mark as brainlist.

Answer 1

Step-by-step explanation:

(1)

Given Equation is a² - 4ab + 4b²

= (a)² - 2(a)(2b) + (2b)²

We know that a² - 2ab + b² = (a - b)²

= (a - 2b)²

(2)

Your Questions seems to be incorrect.It should be 81y⁴.

Given Equation is x⁴ - 18x²y² + 81y⁴

= x⁴ - 9x²y² - 9x²y² + 81y⁴

= x²(x² - 9y²) - 9y²(x² - 9y²)

= (x² - 9y²)(x² - 9y²)

= (x² - (3y)²)(x² - (3y)²)

We know that (a² - b²) = (a + b)(a - b)

= (x - 3y)(x + 3y)(x - 3y)(x + 3y)

= (x - 3y)²(x + 3y)²

(3)

Given Equation is 49a⁶ - 28a³b³ + 4b⁶

= 49a⁶ - 14a³b³ - 14a³b³ + 4b⁶

= 7a³(7a³ - 2b³) - 2b³(7a³ - 2b³)

= (7a³ - 2b³)(7a³ - 2b³)

= (7a³ - 2b³)²

Hope it helps!