Question

factorise the polynomial
$27 - {125a}^{3} - 135a + {225a}^{2}$ please follow me
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Answer 1

for solving this question you should use the polynomial identity (a - b)³ = a³ - b³ -3ab (a-b).

Given, a = 3 ( because 3 is cube root of 27)

b = -5a (because 5 is cube root of 125).

(3)³ - (-5a)³ - 3 (3)(-5a) { 3 + (-5a) }

27 - 125a³ - 45a ( 3 + (-5a) ) = ( multiply 45a with 3 and -5a and get the answer)

27 -125a³ -135a -225 a².

Hence this answer is verified.