Question

pls answer this question??
Factorise the following
(i) 8x3 + 125y3
(ii) 27x3 – 8y3
(iii) a6 – 64
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Answer 1

Step-by-step explanation:

(1) 8x3+125y3

(2x)^3+(5y)^3

(2x+5y)(4x2-10xy+25y2)

(2) (3x)^3-(2y)^3

(3x-2y)(9x2+6xy+4y2)

(3) (a2)^3-(4)^3

(a2-4^2)(a4+a^2.4+16)

(a+4)(a-4)(a4+a^2.4+16)

Answer 2

a³-b³=(a-b)(a²+ab+b²)

a³+b³=(a+b)(a²-ab+b²)

i) (2x)³+(5y)³

=(2x+5y)(2x²-2x.5y+5y²)

=(2x+5y)(4x²-10xy+25y²)

ii) (3x)³- (2y)³

=(3x-2y)(3x²+3x.2y+2y²)

=(3x-2y)(9x²+6xy+4y²)

iii) (a²)³- (4)³

=(a²-4){(a²)²+a².4+(4)²}

=(a²-4)(a⁴+4a²+16)