Question

factorise a²+4b²-4a-4c²
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Answer 1

Answer :

a² + 4b² - 4ab - 4c²

=> a² + (2b)² - 2×a×(2b) - (2c)²

use identity

(a-b)² = a²+b²-2ab

now

=> (a — 2b)² — (2c)²

use identity

a² — b² = (a+b)(a-b)

=> (a — 2b +2c) ( a— 2b — 2c)

is the factor.

Hope my answer have helped you.